[{"publisher":"Shaker","date_created":"2023-02-10T13:05:19Z","title":"Predicting the Bond Quality of Heavy Copper Wire Bonds using a Friction Model Approach","year":"2023","keyword":["heavy copper bonding","wire bonding","quality prediction","friction model","point-contact-element"],"language":[{"iso":"eng"}],"abstract":[{"text":"Ultraschall-Drahtbonden ist eine Standardtechnologie im Bereich der Aufbau- und Verbindungstechnik von Leistungshalbleitermodulen. Um Prozessschritte und damit wertvolle Zeit zu sparen, sollen die Kupferdickdrähte für die Leistungshalbleiter auch für die Kontaktierung von eingespritzten Anschlusssteckern im Modulrahmen verwendet werden. Das Kontaktierungsverfahren mit diesen Drähten auf Steckern in dünnwandigen Kunststoffrahmen führt häufig zu unzureichender Bondqualität. In dieser Arbeit wird das Bonden von Anschlusssteckern experimentell und anhand von Simulationen untersucht, um die Prozessstabilität zu steigern.\r\n\r\nZunächst wurden Experimente auf Untergründen mit hoher Steifigkeit durchgeführt, um Störgrößen von Untergrundeigenschaften zu verringern. Die gewonnenen Erkenntnisse erlaubten die Entwicklung eines Simulationsmodells für die Vorhersage der Bondqualität. Dieses basiert auf einer flächenaufgelösten Reibarbeitsbestimmung im Fügebereich unter Berücksichtigung des Ultraschallerweichungseffektes und der hierdurch entstehenden hohen Drahtverformung.\r\n\r\nExperimente an den Anschlusssteckern im Modulrahmen zeigten eine verringerte Relativverschiebung zwischen Draht und Stecker, was zu einer deutlichen Verringerung der Reibarbeit führt. Außerdem wurden verminderte Schwingamplituden des Bondwerkzeugs nachgewiesen. Dies führt zu einer weiteren Reduktion der Reibarbeit. Beide Effekte wurden mithilfe eines Mehrmassenschwingers modelliert. Die gewonnenen Erkenntnisse und die erstellten Simulationsmodelle ermöglichen die Entwicklung von Klemmvorrichtungen, welche die identifizierten Störgrößen gezielt kompensieren und so ein verlässliches Bonden der Anschlussstecker im gleichen Prozessschritt ermöglichen, in dem auch die Leistungshalbleiter kontaktiert werden.","lang":"ger"}],"date_updated":"2023-02-10T13:05:42Z","supervisor":[{"id":"21220","full_name":"Sextro, Walter","last_name":"Sextro","first_name":"Walter"}],"author":[{"first_name":"Simon","last_name":"Althoff","full_name":"Althoff, Simon"}],"volume":15,"main_file_link":[{"url":"https://katalog.ub.uni-paderborn.de/local/r/9925085762506463?sr[q,any]=Simon%20Althoff"}],"publication_status":"published","publication_identifier":{"isbn":["978-3-8440-8903-5"]},"related_material":{"link":[{"url":"https://www.shaker.de/de/content/catalogue/index.asp?lang=de&ID=8&ISBN=978-3-8440-8903-5&search=yes","relation":"confirmation"}]},"citation":{"apa":"Althoff, S. (2023). <i>Predicting the Bond Quality of Heavy Copper Wire Bonds using a Friction Model Approach</i> (Vol. 15). Shaker.","short":"S. Althoff, Predicting the Bond Quality of Heavy Copper Wire Bonds Using a Friction Model Approach, Shaker, 2023.","mla":"Althoff, Simon. <i>Predicting the Bond Quality of Heavy Copper Wire Bonds Using a Friction Model Approach</i>. Shaker, 2023.","bibtex":"@book{Althoff_2023, series={Schriften des Lehrstuhls für Dynamik und Mechatronik}, title={Predicting the Bond Quality of Heavy Copper Wire Bonds using a Friction Model Approach}, volume={15}, publisher={Shaker}, author={Althoff, Simon}, year={2023}, collection={Schriften des Lehrstuhls für Dynamik und Mechatronik} }","ieee":"S. Althoff, <i>Predicting the Bond Quality of Heavy Copper Wire Bonds using a Friction Model Approach</i>, vol. 15. Shaker, 2023.","chicago":"Althoff, Simon. <i>Predicting the Bond Quality of Heavy Copper Wire Bonds Using a Friction Model Approach</i>. Vol. 15. Schriften Des Lehrstuhls Für Dynamik Und Mechatronik. Shaker, 2023.","ama":"Althoff S. <i>Predicting the Bond Quality of Heavy Copper Wire Bonds Using a Friction Model Approach</i>. Vol 15. Shaker; 2023."},"page":"192","intvolume":"        15","_id":"41971","user_id":"55222","series_title":"Schriften des Lehrstuhls für Dynamik und Mechatronik","department":[{"_id":"151"}],"extern":"1","type":"dissertation","status":"public"},{"title":"Analysis of temperature effect on strength and microstructure in friction induced recycling process (FIRP)","conference":{"location":"Kraków","name":"ESAFORM 2023"},"doi":"10.21741/9781644902479-211","date_updated":"2023-04-26T13:26:22Z","publisher":"Materials Research Forum LLC","author":[{"id":"83141","full_name":"Borgert, Thomas","last_name":"Borgert","first_name":"Thomas"},{"first_name":"Werner","last_name":"Homberg","id":"233","full_name":"Homberg, Werner"}],"date_created":"2023-04-17T08:00:28Z","year":"2023","citation":{"apa":"Borgert, T., &#38; Homberg, W. (2023). Analysis of temperature effect on strength and microstructure in friction induced recycling process (FIRP). <i>Materials Research Proceedings</i>. ESAFORM 2023, Kraków. <a href=\"https://doi.org/10.21741/9781644902479-211\">https://doi.org/10.21741/9781644902479-211</a>","bibtex":"@inproceedings{Borgert_Homberg_2023, title={Analysis of temperature effect on strength and microstructure in friction induced recycling process (FIRP)}, DOI={<a href=\"https://doi.org/10.21741/9781644902479-211\">10.21741/9781644902479-211</a>}, booktitle={Materials Research Proceedings}, publisher={Materials Research Forum LLC}, author={Borgert, Thomas and Homberg, Werner}, year={2023} }","short":"T. Borgert, W. Homberg, in: Materials Research Proceedings, Materials Research Forum LLC, 2023.","mla":"Borgert, Thomas, and Werner Homberg. “Analysis of Temperature Effect on Strength and Microstructure in Friction Induced Recycling Process (FIRP).” <i>Materials Research Proceedings</i>, Materials Research Forum LLC, 2023, doi:<a href=\"https://doi.org/10.21741/9781644902479-211\">10.21741/9781644902479-211</a>.","ama":"Borgert T, Homberg W. Analysis of temperature effect on strength and microstructure in friction induced recycling process (FIRP). In: <i>Materials Research Proceedings</i>. Materials Research Forum LLC; 2023. doi:<a href=\"https://doi.org/10.21741/9781644902479-211\">10.21741/9781644902479-211</a>","ieee":"T. Borgert and W. Homberg, “Analysis of temperature effect on strength and microstructure in friction induced recycling process (FIRP),” presented at the ESAFORM 2023, Kraków, 2023, doi: <a href=\"https://doi.org/10.21741/9781644902479-211\">10.21741/9781644902479-211</a>.","chicago":"Borgert, Thomas, and Werner Homberg. “Analysis of Temperature Effect on Strength and Microstructure in Friction Induced Recycling Process (FIRP).” In <i>Materials Research Proceedings</i>. Materials Research Forum LLC, 2023. <a href=\"https://doi.org/10.21741/9781644902479-211\">https://doi.org/10.21741/9781644902479-211</a>."},"quality_controlled":"1","publication_identifier":{"issn":["2474-395X"]},"publication_status":"published","keyword":["Recycling","Aluminium","Friction-Induced","Energy Efficiency"],"language":[{"iso":"eng"}],"_id":"44036","department":[{"_id":"156"}],"user_id":"83141","abstract":[{"text":"<jats:p>Abstract. In order to reduce global energy consumption in production and industry along with the associated CO2 emissions, existing resources must be used more efficiently. This includes the energy-efficient and comprehensive recycling of a wide range of metals. Especially for the production of aluminium, there is a large potential for saving energy using efficient recycling processes. With regard to the recycling of aluminium studies have shown that solid-state recycling processes are significantly more efficient considering the used energy and resources compared to the conventional, smelting-metallurgical recycling process. In this paper, the direct and energy-efficient friction-induced recycling process (FIRP) based on the conform process is further described and analysed in terms of the temperature-property relationships. For this purpose, the influence of the processing temperature on the microstructure and properties of the recycled semi-finished products is investigated using the toll system that enables an ECAP forming. Specific sections of the (in theory) infinite, recycled semi-finished product are taken and analysed at different process temperatures of the solid state recycling process. Based on these sections, the properties in terms of mechanical hardness, strength, ductility and grain size are analysed and a degressive relationship between process temperature and mechanical hardness up to a temperature of 270 °C can be shown. Applying the Hall-Petch relationship, it is analysed whether there is a correlation between the strength and the microstructure in the form of the grain size. </jats:p>","lang":"eng"}],"status":"public","publication":"Materials Research Proceedings","type":"conference"},{"department":[{"_id":"151"}],"user_id":"210","_id":"21436","language":[{"iso":"eng"}],"keyword":["Ultrasonic heavy wire bonding","Co-simulation","ANSYS","MATLAB","Process optimization","Friction coefficient","Copper-copper","Aluminium-copper"],"publication":"Microelectronics Reliability","type":"journal_article","status":"public","abstract":[{"lang":"eng","text":"Ultrasonic wire bonding is a solid-state joining process, used in the electronics industry to form electrical connections, e.g. to connect electrical terminals within semiconductor modules. Many process parameters affect the bond strength, such like the bond normal force, ultrasonic power, wire material and bonding frequency. Today, process design, development, and optimization is most likely based on the knowledge of process engineers and is mainly performed by experimental testing. In this contribution, a newly developed simulation tool is presented, to reduce time and costs and efficiently determine optimized process parameter. Based on a co-simulation of MATLAB and ANSYS, the different physical phenomena of the wire bonding process are considered using finite element simulation for the complex plastic deformation of the wire and reduced order models for the transient dynamics of the transducer, wire, substrate and bond formation. The model parameters such as the coefficients of friction between bond tool and wire and between wire and substrate were determined for aluminium and copper wire in experiments with a test rig specially developed for the requirements of heavy wire bonding. To reduce simulation time, for the finite element simulation a restart analysis and high performance computing is utilized. Detailed analysis of the bond formation showed, that the normal pressure distribution in the contact between wire and substrate has high impact on bond formation and distribution of welded areas in the contact area."}],"volume":119,"author":[{"id":"28647","full_name":"Schemmel, Reinhard","last_name":"Schemmel","first_name":"Reinhard"},{"first_name":"Viktor","last_name":"Krieger","full_name":"Krieger, Viktor"},{"full_name":"Hemsel, Tobias","id":"210","last_name":"Hemsel","first_name":"Tobias"},{"first_name":"Walter","last_name":"Sextro","full_name":"Sextro, Walter","id":"21220"}],"date_created":"2021-03-10T09:37:02Z","date_updated":"2023-09-21T14:15:33Z","doi":"https://doi.org/10.1016/j.microrel.2021.114077","title":"Co-simulation of MATLAB and ANSYS for ultrasonic wire bonding process optimization","quality_controlled":"1","publication_identifier":{"issn":["0026-2714"]},"publication_status":"published","intvolume":"       119","page":"114077","citation":{"ieee":"R. Schemmel, V. Krieger, T. Hemsel, and W. Sextro, “Co-simulation of MATLAB and ANSYS for ultrasonic wire bonding process optimization,” <i>Microelectronics Reliability</i>, vol. 119, p. 114077, 2021, doi: <a href=\"https://doi.org/10.1016/j.microrel.2021.114077\">https://doi.org/10.1016/j.microrel.2021.114077</a>.","chicago":"Schemmel, Reinhard, Viktor Krieger, Tobias Hemsel, and Walter Sextro. “Co-Simulation of MATLAB and ANSYS for Ultrasonic Wire Bonding Process Optimization.” <i>Microelectronics Reliability</i> 119 (2021): 114077. <a href=\"https://doi.org/10.1016/j.microrel.2021.114077\">https://doi.org/10.1016/j.microrel.2021.114077</a>.","ama":"Schemmel R, Krieger V, Hemsel T, Sextro W. Co-simulation of MATLAB and ANSYS for ultrasonic wire bonding process optimization. <i>Microelectronics Reliability</i>. 2021;119:114077. doi:<a href=\"https://doi.org/10.1016/j.microrel.2021.114077\">https://doi.org/10.1016/j.microrel.2021.114077</a>","apa":"Schemmel, R., Krieger, V., Hemsel, T., &#38; Sextro, W. (2021). Co-simulation of MATLAB and ANSYS for ultrasonic wire bonding process optimization. <i>Microelectronics Reliability</i>, <i>119</i>, 114077. <a href=\"https://doi.org/10.1016/j.microrel.2021.114077\">https://doi.org/10.1016/j.microrel.2021.114077</a>","mla":"Schemmel, Reinhard, et al. “Co-Simulation of MATLAB and ANSYS for Ultrasonic Wire Bonding Process Optimization.” <i>Microelectronics Reliability</i>, vol. 119, 2021, p. 114077, doi:<a href=\"https://doi.org/10.1016/j.microrel.2021.114077\">https://doi.org/10.1016/j.microrel.2021.114077</a>.","short":"R. Schemmel, V. Krieger, T. Hemsel, W. Sextro, Microelectronics Reliability 119 (2021) 114077.","bibtex":"@article{Schemmel_Krieger_Hemsel_Sextro_2021, title={Co-simulation of MATLAB and ANSYS for ultrasonic wire bonding process optimization}, volume={119}, DOI={<a href=\"https://doi.org/10.1016/j.microrel.2021.114077\">https://doi.org/10.1016/j.microrel.2021.114077</a>}, journal={Microelectronics Reliability}, author={Schemmel, Reinhard and Krieger, Viktor and Hemsel, Tobias and Sextro, Walter}, year={2021}, pages={114077} }"},"year":"2021"},{"status":"public","abstract":[{"lang":"eng","text":"The number of multi-material joints is increasing as a result of lightweight design. Self-piercing riveting (SPR) is an important mechanical joining technique for multi-material structures. Rivets for SPR are coated to prevent corrosion, but this coating also influences the friction that prevails during the joining process. The aim of the present investigation is to evaluate this influence. The investigation focuses on the common rivet coatings Almac® and zinc-nickel with topcoat as well as on uncoated rivet surfaces. First of all, the coating thickness and the uniformity of the coating distribution are analysed. Friction tests facilitate the classification of the surface properties. The influence of the friction on the characteristic joint parameters and the force-stroke curves is analysed by means of experimental joining tests. More in-depth knowledge of the effects that occur is achieved through the use of numerical simulation. Overall, it is shown that the surface condition of the rivet has an impact on the friction during the joining process and on the resulting joint. However, the detected deviations between different surface conditions do not restrict the operational capability of SPR and the properties of uncoated rivet surfaces, in particular, are similar to those of Almac®-coated rivets. It can thus be assumed that SPR with respect to the joining process is also possible without rivet coating in principle."}],"publication":"Key Engineering Materials","type":"journal_article","language":[{"iso":"eng"}],"keyword":["Coating","Friction","Joining"],"department":[{"_id":"157"}],"user_id":"53912","_id":"22272","page":"11-18","intvolume":"       883","citation":{"mla":"Uhe, Benedikt, et al. “Influence of the Rivet Coating on the Friction during Self-Piercing Riveting.” <i>Key Engineering Materials</i>, vol. 883, 2021, pp. 11–18, doi:<a href=\"https://doi.org/10.4028/www.scientific.net/KEM.883.11\">10.4028/www.scientific.net/KEM.883.11</a>.","short":"B. Uhe, C.-M. Kuball, M. Merklein, G. Meschut, Key Engineering Materials 883 (2021) 11–18.","bibtex":"@article{Uhe_Kuball_Merklein_Meschut_2021, title={Influence of the Rivet Coating on the Friction during Self-Piercing Riveting}, volume={883}, DOI={<a href=\"https://doi.org/10.4028/www.scientific.net/KEM.883.11\">10.4028/www.scientific.net/KEM.883.11</a>}, journal={Key Engineering Materials}, author={Uhe, Benedikt and Kuball, Clara-Maria and Merklein, Marion and Meschut, Gerson}, year={2021}, pages={11–18} }","apa":"Uhe, B., Kuball, C.-M., Merklein, M., &#38; Meschut, G. (2021). Influence of the Rivet Coating on the Friction during Self-Piercing Riveting. <i>Key Engineering Materials</i>, <i>883</i>, 11–18. <a href=\"https://doi.org/10.4028/www.scientific.net/KEM.883.11\">https://doi.org/10.4028/www.scientific.net/KEM.883.11</a>","ama":"Uhe B, Kuball C-M, Merklein M, Meschut G. Influence of the Rivet Coating on the Friction during Self-Piercing Riveting. <i>Key Engineering Materials</i>. 2021;883:11-18. doi:<a href=\"https://doi.org/10.4028/www.scientific.net/KEM.883.11\">10.4028/www.scientific.net/KEM.883.11</a>","chicago":"Uhe, Benedikt, Clara-Maria Kuball, Marion Merklein, and Gerson Meschut. “Influence of the Rivet Coating on the Friction during Self-Piercing Riveting.” <i>Key Engineering Materials</i> 883 (2021): 11–18. <a href=\"https://doi.org/10.4028/www.scientific.net/KEM.883.11\">https://doi.org/10.4028/www.scientific.net/KEM.883.11</a>.","ieee":"B. Uhe, C.-M. Kuball, M. Merklein, and G. Meschut, “Influence of the Rivet Coating on the Friction during Self-Piercing Riveting,” <i>Key Engineering Materials</i>, vol. 883, pp. 11–18, 2021, doi: <a href=\"https://doi.org/10.4028/www.scientific.net/KEM.883.11\">10.4028/www.scientific.net/KEM.883.11</a>."},"year":"2021","quality_controlled":"1","doi":"10.4028/www.scientific.net/KEM.883.11","title":"Influence of the Rivet Coating on the Friction during Self-Piercing Riveting","volume":883,"author":[{"id":"38131","full_name":"Uhe, Benedikt","last_name":"Uhe","first_name":"Benedikt"},{"full_name":"Kuball, Clara-Maria","last_name":"Kuball","first_name":"Clara-Maria"},{"full_name":"Merklein, Marion","last_name":"Merklein","first_name":"Marion"},{"last_name":"Meschut","orcid":"0000-0002-2763-1246","id":"32056","full_name":"Meschut, Gerson","first_name":"Gerson"}],"date_created":"2021-05-31T10:06:11Z","date_updated":"2026-02-27T10:23:33Z"},{"language":[{"iso":"eng"}],"keyword":["Ultrasonic bonding","Ultrasonic welding","Multi-dimensional bonding","Complex vibration","Multi-frequent","Two-dimensional friction model"],"department":[{"_id":"151"}],"user_id":"210","_id":"10334","project":[{"_id":"93","name":"Hochleistungsbonden in energieeffizienten Leistungshalbleitermodulen","grant_number":"MP-1-1-015"}],"status":"public","abstract":[{"lang":"eng","text":"Ultrasonic joining is a common industrial process. In the electronics industry it is used to form electrical connections, including those of dissimilar materials. Multiple influencing factors in ultrasonic joining are known and extensively investigated; process parameters like ultrasonic power, bond force, and bonding frequency of the ultrasonic vibration are known to have a high impact on a reliable joining process and need to be adapted for each new application with different geometry or materials. This contribution is focused on increasing ultrasonic power transmitted to the interface and keeping mechanical stresses during ultrasonic bonding low by using a multi-dimensional ultrasonic transducer concept. Bonding results for a new designed connector pin in IGBT-modules achieved by multi- and one-dimensional bonding are discussed."}],"publication":"Sensors and Actuators A: Physical","type":"journal_article","doi":"10.1016/j.sna.2019.04.025","title":"Using complex multi-dimensional vibration trajectories in ultrasonic bonding and welding","volume":295,"author":[{"first_name":"Reinhard","id":"28647","full_name":"Schemmel, Reinhard","last_name":"Schemmel"},{"first_name":"Tobias","last_name":"Hemsel","full_name":"Hemsel, Tobias","id":"210"},{"full_name":"Dymel, Collin","id":"66833","last_name":"Dymel","first_name":"Collin"},{"last_name":"Hunstig","full_name":"Hunstig, Matthias","first_name":"Matthias"},{"full_name":"Brökelmann, Michael","last_name":"Brökelmann","first_name":"Michael"},{"first_name":"Walter","last_name":"Sextro","full_name":"Sextro, Walter","id":"21220"}],"date_created":"2019-07-01T07:32:07Z","date_updated":"2023-09-21T14:12:15Z","page":"653 - 662","intvolume":"       295","citation":{"short":"R. Schemmel, T. Hemsel, C. Dymel, M. Hunstig, M. Brökelmann, W. Sextro, Sensors and Actuators A: Physical 295 (2019) 653–662.","mla":"Schemmel, Reinhard, et al. “Using Complex Multi-Dimensional Vibration Trajectories in Ultrasonic Bonding and Welding.” <i>Sensors and Actuators A: Physical</i>, vol. 295, 2019, pp. 653–62, doi:<a href=\"https://doi.org/10.1016/j.sna.2019.04.025\">10.1016/j.sna.2019.04.025</a>.","bibtex":"@article{Schemmel_Hemsel_Dymel_Hunstig_Brökelmann_Sextro_2019, title={Using complex multi-dimensional vibration trajectories in ultrasonic bonding and welding}, volume={295}, DOI={<a href=\"https://doi.org/10.1016/j.sna.2019.04.025\">10.1016/j.sna.2019.04.025</a>}, journal={Sensors and Actuators A: Physical}, author={Schemmel, Reinhard and Hemsel, Tobias and Dymel, Collin and Hunstig, Matthias and Brökelmann, Michael and Sextro, Walter}, year={2019}, pages={653–662} }","apa":"Schemmel, R., Hemsel, T., Dymel, C., Hunstig, M., Brökelmann, M., &#38; Sextro, W. (2019). Using complex multi-dimensional vibration trajectories in ultrasonic bonding and welding. <i>Sensors and Actuators A: Physical</i>, <i>295</i>, 653–662. <a href=\"https://doi.org/10.1016/j.sna.2019.04.025\">https://doi.org/10.1016/j.sna.2019.04.025</a>","chicago":"Schemmel, Reinhard, Tobias Hemsel, Collin Dymel, Matthias Hunstig, Michael Brökelmann, and Walter Sextro. “Using Complex Multi-Dimensional Vibration Trajectories in Ultrasonic Bonding and Welding.” <i>Sensors and Actuators A: Physical</i> 295 (2019): 653–62. <a href=\"https://doi.org/10.1016/j.sna.2019.04.025\">https://doi.org/10.1016/j.sna.2019.04.025</a>.","ieee":"R. Schemmel, T. Hemsel, C. Dymel, M. Hunstig, M. Brökelmann, and W. Sextro, “Using complex multi-dimensional vibration trajectories in ultrasonic bonding and welding,” <i>Sensors and Actuators A: Physical</i>, vol. 295, pp. 653–662, 2019, doi: <a href=\"https://doi.org/10.1016/j.sna.2019.04.025\">10.1016/j.sna.2019.04.025</a>.","ama":"Schemmel R, Hemsel T, Dymel C, Hunstig M, Brökelmann M, Sextro W. Using complex multi-dimensional vibration trajectories in ultrasonic bonding and welding. <i>Sensors and Actuators A: Physical</i>. 2019;295:653-662. doi:<a href=\"https://doi.org/10.1016/j.sna.2019.04.025\">10.1016/j.sna.2019.04.025</a>"},"year":"2019","publication_identifier":{"issn":["0924-4247"]},"quality_controlled":"1"},{"date_created":"2026-02-07T15:40:18Z","author":[{"last_name":"Hadjiali","full_name":"Hadjiali, S.","first_name":"S."},{"first_name":"R.","last_name":"Savka","full_name":"Savka, R."},{"last_name":"Plaumann","full_name":"Plaumann, M.","first_name":"M."},{"first_name":"U.","full_name":"Bommerich, U.","last_name":"Bommerich"},{"first_name":"S.","full_name":"Bothe, S.","last_name":"Bothe"},{"full_name":"Gutmann, Torsten","id":"118165","last_name":"Gutmann","first_name":"Torsten"},{"first_name":"T.","full_name":"Ratajczyk, T.","last_name":"Ratajczyk"},{"last_name":"Bernarding","full_name":"Bernarding, J.","first_name":"J."},{"first_name":"H. H.","full_name":"Limbach, H. H.","last_name":"Limbach"},{"first_name":"H.","full_name":"Plenio, H.","last_name":"Plenio"},{"first_name":"G.","last_name":"Buntkowsky","full_name":"Buntkowsky, G."}],"volume":50,"date_updated":"2026-02-17T16:17:34Z","doi":"10.1007/s00723-019-01115-x","title":"Substituent Influences on the NMR Signal Amplification of Ir Complexes with Heterocyclic Carbene Ligands","issue":"7","publication_identifier":{"issn":["1613-7507"]},"citation":{"ama":"Hadjiali S, Savka R, Plaumann M, et al. Substituent Influences on the NMR Signal Amplification of Ir Complexes with Heterocyclic Carbene Ligands. <i>Applied Magnetic Resonance</i>. 2019;50(7):895–902. doi:<a href=\"https://doi.org/10.1007/s00723-019-01115-x\">10.1007/s00723-019-01115-x</a>","chicago":"Hadjiali, S., R. Savka, M. Plaumann, U. Bommerich, S. Bothe, Torsten Gutmann, T. Ratajczyk, et al. “Substituent Influences on the NMR Signal Amplification of Ir Complexes with Heterocyclic Carbene Ligands.” <i>Applied Magnetic Resonance</i> 50, no. 7 (2019): 895–902. <a href=\"https://doi.org/10.1007/s00723-019-01115-x\">https://doi.org/10.1007/s00723-019-01115-x</a>.","ieee":"S. Hadjiali <i>et al.</i>, “Substituent Influences on the NMR Signal Amplification of Ir Complexes with Heterocyclic Carbene Ligands,” <i>Applied Magnetic Resonance</i>, vol. 50, no. 7, pp. 895–902, 2019, doi: <a href=\"https://doi.org/10.1007/s00723-019-01115-x\">10.1007/s00723-019-01115-x</a>.","mla":"Hadjiali, S., et al. “Substituent Influences on the NMR Signal Amplification of Ir Complexes with Heterocyclic Carbene Ligands.” <i>Applied Magnetic Resonance</i>, vol. 50, no. 7, 2019, pp. 895–902, doi:<a href=\"https://doi.org/10.1007/s00723-019-01115-x\">10.1007/s00723-019-01115-x</a>.","short":"S. Hadjiali, R. Savka, M. Plaumann, U. Bommerich, S. Bothe, T. Gutmann, T. Ratajczyk, J. Bernarding, H.H. Limbach, H. Plenio, G. Buntkowsky, Applied Magnetic Resonance 50 (2019) 895–902.","bibtex":"@article{Hadjiali_Savka_Plaumann_Bommerich_Bothe_Gutmann_Ratajczyk_Bernarding_Limbach_Plenio_et al._2019, title={Substituent Influences on the NMR Signal Amplification of Ir Complexes with Heterocyclic Carbene Ligands}, volume={50}, DOI={<a href=\"https://doi.org/10.1007/s00723-019-01115-x\">10.1007/s00723-019-01115-x</a>}, number={7}, journal={Applied Magnetic Resonance}, author={Hadjiali, S. and Savka, R. and Plaumann, M. and Bommerich, U. and Bothe, S. and Gutmann, Torsten and Ratajczyk, T. and Bernarding, J. and Limbach, H. H. and Plenio, H. and et al.}, year={2019}, pages={895–902} }","apa":"Hadjiali, S., Savka, R., Plaumann, M., Bommerich, U., Bothe, S., Gutmann, T., Ratajczyk, T., Bernarding, J., Limbach, H. H., Plenio, H., &#38; Buntkowsky, G. (2019). Substituent Influences on the NMR Signal Amplification of Ir Complexes with Heterocyclic Carbene Ligands. <i>Applied Magnetic Resonance</i>, <i>50</i>(7), 895–902. <a href=\"https://doi.org/10.1007/s00723-019-01115-x\">https://doi.org/10.1007/s00723-019-01115-x</a>"},"intvolume":"        50","page":"895–902","year":"2019","user_id":"100715","_id":"63969","extern":"1","language":[{"iso":"eng"}],"keyword":["dynamic nuclear-polarization","hyperpolarization","enhancement","hydrogen induced polarization","olefin-metathesis catalysts","parahydrogen-induced polarization","peptides","Physics","sabre","spectroscopy"],"type":"journal_article","publication":"Applied Magnetic Resonance","status":"public","abstract":[{"text":"A number of Ir-N-heterocyclic carbene (Ir-NHC) complexes with asymmetric N-heterocyclic carbene (NHC) ligands have been prepared and examined for signal amplification by reversible exchange (SABRE). Pyridine was chosen as model compound for hyperpolarization experiments. This substrate was examined in a solvent mixture using several Ir-NHC complexes, which differ in their NHC ligands. The SABRE polarization was created at 6mT and the H-1 nuclear magnetic resonancesignals were detected at 7T. We show that asymmetric NHC ligands, because of their favorable chemistry, can adapt the SABREactive complexes to different chemical scenarios.","lang":"eng"}]},{"year":"2015","citation":{"ieee":"F. Schulte, J. Neuhaus, and W. Sextro, “A Mechanical Model for the Dynamical Contact of Elastic Rough Bodies with Viscoelastic Properties,” in <i>Proceedings of ICoEV 2015 International Conference on Engineering Vibration</i>, 2015, pp. 1109–1117.","chicago":"Schulte, Frank, Jan Neuhaus, and Walter Sextro. “A Mechanical Model for the Dynamical Contact of Elastic Rough Bodies with Viscoelastic Properties.” In <i>Proceedings of ICoEV 2015 International Conference on Engineering Vibration</i>, 1109–17, 2015.","ama":"Schulte F, Neuhaus J, Sextro W. A Mechanical Model for the Dynamical Contact of Elastic Rough Bodies with Viscoelastic Properties. In: <i>Proceedings of ICoEV 2015 International Conference on Engineering Vibration</i>. ; 2015:1109-1117.","apa":"Schulte, F., Neuhaus, J., &#38; Sextro, W. (2015). A Mechanical Model for the Dynamical Contact of Elastic Rough Bodies with Viscoelastic Properties. In <i>Proceedings of ICoEV 2015 International Conference on Engineering Vibration</i> (pp. 1109–1117).","mla":"Schulte, Frank, et al. “A Mechanical Model for the Dynamical Contact of Elastic Rough Bodies with Viscoelastic Properties.” <i>Proceedings of ICoEV 2015 International Conference on Engineering Vibration</i>, 2015, pp. 1109–17.","bibtex":"@inproceedings{Schulte_Neuhaus_Sextro_2015, title={A Mechanical Model for the Dynamical Contact of Elastic Rough Bodies with Viscoelastic Properties}, booktitle={Proceedings of ICoEV 2015 International Conference on Engineering Vibration}, author={Schulte, Frank and Neuhaus, Jan and Sextro, Walter}, year={2015}, pages={1109–1117} }","short":"F. Schulte, J. Neuhaus, W. Sextro, in: Proceedings of ICoEV 2015 International Conference on Engineering Vibration, 2015, pp. 1109–1117."},"page":"1109-1117","quality_controlled":"1","title":"A Mechanical Model for the Dynamical Contact of Elastic Rough Bodies with Viscoelastic Properties","date_updated":"2019-09-16T10:47:53Z","date_created":"2019-05-27T08:37:22Z","author":[{"last_name":"Schulte","full_name":"Schulte, Frank","first_name":"Frank"},{"first_name":"Jan","last_name":"Neuhaus","full_name":"Neuhaus, Jan"},{"first_name":"Walter","last_name":"Sextro","full_name":"Sextro, Walter","id":"21220"}],"abstract":[{"lang":"eng","text":"The contact between viscoelastic materials e.g. elastomers and a rough surface leads to a special friction characteristic, which differs greatly in its properties comparing to other materials like metals. In practice, this friction combination occurs for example in the tire-road contact, or in the use of rubber gaskets. Due to the frictional forces a system is significantly influenced in its vibrational properties. The friction force is composed of two main components adhesion and hysteresis. The adhesion results from molecular bounds between the contact partners, while the deformation of the viscoelastic material by the roughness of the counter body leads to power loss. This internal friction results in an additional frictional force, which is described by the hysteresis. To simulate the frictional behaviour of elastomers on rough surfaces and thus to determine the energy dissipation in contact, it is necessary to develop a mechanical model which considers the roughness of the contact partners, as well as dynamic effects and the dependence on normal pressure and sliding speed. The viscoelastic material behaviour must also be considered. The contact between two rough surfaces is modelled as a rough rigid layer contacting a rough elas- tic layer. The elastic layer is modelled by point masses connected by Maxwell-elements. This allows the viscoelastic properties of the elastomer to be considered. The behaviour of whole system can be described by equations of motion with integrated constraints. The degrees of freedom of the model depends on the varying contact conditions. A point mass not in contact has two degrees of freedom. A point mass in contact moving along the roughness path can be described by only one degree of freedom. For each Maxwell-Element also an inner coordinate and thus a further degree of freedom is needed. Because of varying contact conditions dur- ing the simulation, the simulation interrupts in case the contact conditions change. Then the equations of motions are adapted with respect to the contact constraints. As a result of the simulation one obtain the energy dissipation and thus the friction char- acteristic during the friction process. It is possible to use these results in three dimensional point-contact elements in order to model contact surfaces on lager length scales."}],"status":"public","type":"conference","publication":"Proceedings of ICoEV 2015 International Conference on Engineering Vibration","keyword":["Contact Mechanics","Viscoelastic Material","Adhesive Friction","Hysteresis Friction","Energy Dissipation","Vibration"],"language":[{"iso":"eng"}],"_id":"9952","user_id":"55222","department":[{"_id":"151"}]},{"volume":"328-329","author":[{"full_name":"Frölich, D.","last_name":"Frölich","first_name":"D."},{"id":"97759","full_name":"Magyar, Balázs","last_name":"Magyar","first_name":"Balázs"},{"last_name":"Sauer","full_name":"Sauer, B.","first_name":"B."},{"first_name":"P.","full_name":"Mayer, P.","last_name":"Mayer"},{"last_name":"Kirsch","full_name":"Kirsch, B.","first_name":"B."},{"first_name":"J.C.","last_name":"Aurich","full_name":"Aurich, J.C."},{"first_name":"R.","full_name":"Skorupski, R.","last_name":"Skorupski"},{"first_name":"M.","last_name":"Smaga","full_name":"Smaga, M."},{"full_name":"Beck, T.","last_name":"Beck","first_name":"T."},{"last_name":"Eifler","full_name":"Eifler, D.","first_name":"D."}],"date_created":"2022-12-15T10:17:23Z","date_updated":"2022-12-15T10:18:54Z","doi":"https://doi.org/10.1016/j.wear.2015.02.004","title":"Investigation of wear resistance of dry and cryogenic turned metastable austenitic steel shafts and dry turned and ground carburized steel shafts in the radial shaft seal ring system","publication_identifier":{"issn":["0043-1648"]},"page":"123-131","citation":{"ama":"Frölich D, Magyar B, Sauer B, et al. Investigation of wear resistance of dry and cryogenic turned metastable austenitic steel shafts and dry turned and ground carburized steel shafts in the radial shaft seal ring system. <i>Wear</i>. 2015;328-329:123-131. doi:<a href=\"https://doi.org/10.1016/j.wear.2015.02.004\">https://doi.org/10.1016/j.wear.2015.02.004</a>","chicago":"Frölich, D., Balázs Magyar, B. Sauer, P. Mayer, B. Kirsch, J.C. Aurich, R. Skorupski, M. Smaga, T. Beck, and D. Eifler. “Investigation of Wear Resistance of Dry and Cryogenic Turned Metastable Austenitic Steel Shafts and Dry Turned and Ground Carburized Steel Shafts in the Radial Shaft Seal Ring System.” <i>Wear</i> 328–329 (2015): 123–31. <a href=\"https://doi.org/10.1016/j.wear.2015.02.004\">https://doi.org/10.1016/j.wear.2015.02.004</a>.","ieee":"D. Frölich <i>et al.</i>, “Investigation of wear resistance of dry and cryogenic turned metastable austenitic steel shafts and dry turned and ground carburized steel shafts in the radial shaft seal ring system,” <i>Wear</i>, vol. 328–329, pp. 123–131, 2015, doi: <a href=\"https://doi.org/10.1016/j.wear.2015.02.004\">https://doi.org/10.1016/j.wear.2015.02.004</a>.","mla":"Frölich, D., et al. “Investigation of Wear Resistance of Dry and Cryogenic Turned Metastable Austenitic Steel Shafts and Dry Turned and Ground Carburized Steel Shafts in the Radial Shaft Seal Ring System.” <i>Wear</i>, vol. 328–329, 2015, pp. 123–31, doi:<a href=\"https://doi.org/10.1016/j.wear.2015.02.004\">https://doi.org/10.1016/j.wear.2015.02.004</a>.","bibtex":"@article{Frölich_Magyar_Sauer_Mayer_Kirsch_Aurich_Skorupski_Smaga_Beck_Eifler_2015, title={Investigation of wear resistance of dry and cryogenic turned metastable austenitic steel shafts and dry turned and ground carburized steel shafts in the radial shaft seal ring system}, volume={328–329}, DOI={<a href=\"https://doi.org/10.1016/j.wear.2015.02.004\">https://doi.org/10.1016/j.wear.2015.02.004</a>}, journal={Wear}, author={Frölich, D. and Magyar, Balázs and Sauer, B. and Mayer, P. and Kirsch, B. and Aurich, J.C. and Skorupski, R. and Smaga, M. and Beck, T. and Eifler, D.}, year={2015}, pages={123–131} }","short":"D. Frölich, B. Magyar, B. Sauer, P. Mayer, B. Kirsch, J.C. Aurich, R. Skorupski, M. Smaga, T. Beck, D. Eifler, Wear 328–329 (2015) 123–131.","apa":"Frölich, D., Magyar, B., Sauer, B., Mayer, P., Kirsch, B., Aurich, J. C., Skorupski, R., Smaga, M., Beck, T., &#38; Eifler, D. (2015). Investigation of wear resistance of dry and cryogenic turned metastable austenitic steel shafts and dry turned and ground carburized steel shafts in the radial shaft seal ring system. <i>Wear</i>, <i>328–329</i>, 123–131. <a href=\"https://doi.org/10.1016/j.wear.2015.02.004\">https://doi.org/10.1016/j.wear.2015.02.004</a>"},"year":"2015","department":[{"_id":"146"}],"user_id":"38077","_id":"34441","language":[{"iso":"eng"}],"extern":"1","keyword":["Radial shaft seal ring","Shaft surface","Cryogenic turning","Metastable austenitic steel","Deformation-induced martensite formation"],"publication":"Wear","type":"journal_article","status":"public","abstract":[{"text":"The state of the art industrial manufacturing process to produce shafts as counter surfaces for radial shaft seal rings is plunge grinding. This process consists of three major steps. The blank is turned to a slight diameter-oversize followed by the heat treatment and the hard-finishing by plunge grinding. The geometric surface structures of the resulting shafts in general exhibit a stochastic distribution. These surface characteristics contribute to a reliable and stable sealing functionality. And the surface and subsurface hardness generally leads to a higher wear resistance of the shaft. Motivated by economic benefits and in order to achieve a compact production process for at least ten years, turning is investigated as an alternative manufacturing process. However due to the resulting lead structure on the shaft surface and the associated risk of leakage it has not become prevalent yet. In this paper turned shafts of the metastable austenitic steel AISI 347 (1.4550, X6CrNiNb1810) are investigated as alternative material for counter surfaces of radial shaft seal rings and compared to turned shafts of carburized AISI 5115 (1.7131, 16MnCr5). In addition to surfaces dry turned at room-temperature, cryogenic turned AISI 347 counter surfaces are analyzed. By applying cryogenic cooling, the formation of deformation-induced α′-martensite in the surface layer is possible during the turning process. Endurance tests in radial shaft seal ring test rigs are performed and complemented with detailed investigations of microstructure, micro-hardness and surface topography. The results are compared to results of state of the art ground AISI 5115 shafts.","lang":"eng"}]},{"keyword":["adhesion","circuit reliability","deformation","diffusion","fatigue cracks","friction","interconnections","lead bonding","van der Waals forces","Cu","adhering process","adhesion process","ampacity improvement","bond quality improvement","cleaning process","diffusing process","fatigue fracture failure","friction energy","friction model","heat dissipation","mechanical strength","piezoelectric triaxial force sensor","predeforming process","size 500 mum","total contact area","van der Waals forces","wedge copper wire bonding","Bonding","Copper","Finite element analysis","Force","Friction","Substrates","Wires"],"language":[{"iso":"eng"}],"_id":"9868","department":[{"_id":"151"}],"user_id":"55222","abstract":[{"lang":"eng","text":"In order to increase mechanical strength, heat dissipation and ampacity and to decrease failure through fatigue fracture, wedge copper wire bonding is being introduced as a standard interconnection method for mass production. To achieve the same process stability when using copper wire instead of aluminum wire a profound understanding of the bonding process is needed. Due to the higher hardness of copper compared to aluminum wire it is more difficult to approach the surfaces of wire and substrate to a level where van der Waals forces are able to arise between atoms. Also, enough friction energy referred to the total contact area has to be generated to activate the surfaces. Therefore, a friction model is used to simulate the joining process. This model calculates the resulting energy of partial areas in the contact surface and provides information about the adhesion process of each area. The focus here is on the arising of micro joints in the contact area depending on the location in the contact and time. To validate the model, different touchdown forces are used to vary the initial contact areas of wire and substrate. Additionally, a piezoelectric tri-axial force sensor is built up to identify the known phases of pre-deforming, cleaning, adhering and diffusing for the real bonding process to map with the model. Test substrates as DBC and copper plate are used to show the different formations of a wedge bond connection due to hardness and reaction propensity. The experiments were done by using 500 $\\mu$m copper wire and a standard V-groove tool."}],"status":"public","publication":"Electronic Components and Technology Conference (ECTC), 2014 IEEE 64th","type":"conference","title":"Improving the bond quality of copper wire bonds using a friction model approach","doi":"10.1109/ECTC.2014.6897500","date_updated":"2019-09-16T10:57:58Z","author":[{"last_name":"Althoff","full_name":"Althoff, Simon","first_name":"Simon"},{"first_name":"Jan","last_name":"Neuhaus","full_name":"Neuhaus, Jan"},{"last_name":"Hemsel","full_name":"Hemsel, Tobias","id":"210","first_name":"Tobias"},{"first_name":"Walter","last_name":"Sextro","id":"21220","full_name":"Sextro, Walter"}],"date_created":"2019-05-20T12:11:44Z","year":"2014","page":"1549-1555","citation":{"apa":"Althoff, S., Neuhaus, J., Hemsel, T., &#38; Sextro, W. (2014). Improving the bond quality of copper wire bonds using a friction model approach. In <i>Electronic Components and Technology Conference (ECTC), 2014 IEEE 64th</i> (pp. 1549–1555). <a href=\"https://doi.org/10.1109/ECTC.2014.6897500\">https://doi.org/10.1109/ECTC.2014.6897500</a>","bibtex":"@inproceedings{Althoff_Neuhaus_Hemsel_Sextro_2014, title={Improving the bond quality of copper wire bonds using a friction model approach}, DOI={<a href=\"https://doi.org/10.1109/ECTC.2014.6897500\">10.1109/ECTC.2014.6897500</a>}, booktitle={Electronic Components and Technology Conference (ECTC), 2014 IEEE 64th}, author={Althoff, Simon and Neuhaus, Jan and Hemsel, Tobias and Sextro, Walter}, year={2014}, pages={1549–1555} }","short":"S. Althoff, J. Neuhaus, T. Hemsel, W. Sextro, in: Electronic Components and Technology Conference (ECTC), 2014 IEEE 64th, 2014, pp. 1549–1555.","mla":"Althoff, Simon, et al. “Improving the Bond Quality of Copper Wire Bonds Using a Friction Model Approach.” <i>Electronic Components and Technology Conference (ECTC), 2014 IEEE 64th</i>, 2014, pp. 1549–55, doi:<a href=\"https://doi.org/10.1109/ECTC.2014.6897500\">10.1109/ECTC.2014.6897500</a>.","ama":"Althoff S, Neuhaus J, Hemsel T, Sextro W. Improving the bond quality of copper wire bonds using a friction model approach. In: <i>Electronic Components and Technology Conference (ECTC), 2014 IEEE 64th</i>. ; 2014:1549-1555. doi:<a href=\"https://doi.org/10.1109/ECTC.2014.6897500\">10.1109/ECTC.2014.6897500</a>","chicago":"Althoff, Simon, Jan Neuhaus, Tobias Hemsel, and Walter Sextro. “Improving the Bond Quality of Copper Wire Bonds Using a Friction Model Approach.” In <i>Electronic Components and Technology Conference (ECTC), 2014 IEEE 64th</i>, 1549–55, 2014. <a href=\"https://doi.org/10.1109/ECTC.2014.6897500\">https://doi.org/10.1109/ECTC.2014.6897500</a>.","ieee":"S. Althoff, J. Neuhaus, T. Hemsel, and W. Sextro, “Improving the bond quality of copper wire bonds using a friction model approach,” in <i>Electronic Components and Technology Conference (ECTC), 2014 IEEE 64th</i>, 2014, pp. 1549–1555."},"quality_controlled":"1"},{"_id":"9876","department":[{"_id":"151"}],"user_id":"55222","keyword":["Inertia motor","High velocity","Stick-slip motor","Slip-slip operation","Friction parameter identification"],"language":[{"iso":"eng"}],"publication":"Archive of Applied Mechanics","type":"journal_article","abstract":[{"lang":"eng","text":"Piezoelectric inertia motors use the inertia of a body to drive it by means of a friction contact in a series of small steps. It has been shown previously in theoretical investigations that higher velocities and smoother movements can be obtained if these steps do not contain phases of stiction (''stick-slip`` operation), but use sliding friction only (''slip-slip`` operation). One very promising driving option for such motors is the superposition of multiple sinusoidal signals or harmonics. In this contribution, the theoretical results are validated experimentally. In this context, a quick and reliable identification process for parameters describing the friction contact is proposed. Additionally, the force generation potential of inertia motors is investigated theoretically and experimentally. The experimental results confirm the theoretical result that for a given maximum frequency, a signal with a high fundamental frequency and consisting of two superposed sine waves leads to the highest velocity and the smoothest motion, while the maximum motor force is obtained with signals containing more harmonics. These results are of fundamental importance for the further development of high-velocity piezoelectric inertia motors."}],"status":"public","date_updated":"2019-05-20T13:08:43Z","publisher":"Springer Berlin Heidelberg","author":[{"first_name":"Matthias","full_name":"Hunstig, Matthias","last_name":"Hunstig"},{"full_name":"Hemsel, Tobias","id":"210","last_name":"Hemsel","first_name":"Tobias"},{"id":"21220","full_name":"Sextro, Walter","last_name":"Sextro","first_name":"Walter"}],"date_created":"2019-05-20T13:08:08Z","title":"High-velocity operation of piezoelectric inertia motors: experimental validation","doi":"10.1007/s00419-014-0940-0","publication_identifier":{"issn":["0939-1533"]},"year":"2014","page":"1-9","citation":{"mla":"Hunstig, Matthias, et al. “High-Velocity Operation of Piezoelectric Inertia Motors: Experimental Validation.” <i>Archive of Applied Mechanics</i>, Springer Berlin Heidelberg, 2014, pp. 1–9, doi:<a href=\"https://doi.org/10.1007/s00419-014-0940-0\">10.1007/s00419-014-0940-0</a>.","short":"M. Hunstig, T. Hemsel, W. Sextro, Archive of Applied Mechanics (2014) 1–9.","bibtex":"@article{Hunstig_Hemsel_Sextro_2014, title={High-velocity operation of piezoelectric inertia motors: experimental validation}, DOI={<a href=\"https://doi.org/10.1007/s00419-014-0940-0\">10.1007/s00419-014-0940-0</a>}, journal={Archive of Applied Mechanics}, publisher={Springer Berlin Heidelberg}, author={Hunstig, Matthias and Hemsel, Tobias and Sextro, Walter}, year={2014}, pages={1–9} }","apa":"Hunstig, M., Hemsel, T., &#38; Sextro, W. (2014). High-velocity operation of piezoelectric inertia motors: experimental validation. <i>Archive of Applied Mechanics</i>, 1–9. <a href=\"https://doi.org/10.1007/s00419-014-0940-0\">https://doi.org/10.1007/s00419-014-0940-0</a>","ama":"Hunstig M, Hemsel T, Sextro W. High-velocity operation of piezoelectric inertia motors: experimental validation. <i>Archive of Applied Mechanics</i>. 2014:1-9. doi:<a href=\"https://doi.org/10.1007/s00419-014-0940-0\">10.1007/s00419-014-0940-0</a>","ieee":"M. Hunstig, T. Hemsel, and W. Sextro, “High-velocity operation of piezoelectric inertia motors: experimental validation,” <i>Archive of Applied Mechanics</i>, pp. 1–9, 2014.","chicago":"Hunstig, Matthias, Tobias Hemsel, and Walter Sextro. “High-Velocity Operation of Piezoelectric Inertia Motors: Experimental Validation.” <i>Archive of Applied Mechanics</i>, 2014, 1–9. <a href=\"https://doi.org/10.1007/s00419-014-0940-0\">https://doi.org/10.1007/s00419-014-0940-0</a>."}},{"title":"A comprehensive model of wear, friction and contact temperature in radial shaft seals","doi":"https://doi.org/10.1016/j.wear.2013.12.030","date_updated":"2022-12-15T10:20:39Z","author":[{"first_name":"D.","full_name":"Frölich, D.","last_name":"Frölich"},{"last_name":"Magyar","id":"97759","full_name":"Magyar, Balázs","first_name":"Balázs"},{"full_name":"Sauer, B.","last_name":"Sauer","first_name":"B."}],"date_created":"2022-12-15T10:19:37Z","volume":311,"year":"2014","citation":{"mla":"Frölich, D., et al. “A Comprehensive Model of Wear, Friction and Contact Temperature in Radial Shaft Seals.” <i>Wear</i>, vol. 311, no. 1, 2014, pp. 71–80, doi:<a href=\"https://doi.org/10.1016/j.wear.2013.12.030\">https://doi.org/10.1016/j.wear.2013.12.030</a>.","short":"D. Frölich, B. Magyar, B. Sauer, Wear 311 (2014) 71–80.","bibtex":"@article{Frölich_Magyar_Sauer_2014, title={A comprehensive model of wear, friction and contact temperature in radial shaft seals}, volume={311}, DOI={<a href=\"https://doi.org/10.1016/j.wear.2013.12.030\">https://doi.org/10.1016/j.wear.2013.12.030</a>}, number={1}, journal={Wear}, author={Frölich, D. and Magyar, Balázs and Sauer, B.}, year={2014}, pages={71–80} }","apa":"Frölich, D., Magyar, B., &#38; Sauer, B. (2014). A comprehensive model of wear, friction and contact temperature in radial shaft seals. <i>Wear</i>, <i>311</i>(1), 71–80. <a href=\"https://doi.org/10.1016/j.wear.2013.12.030\">https://doi.org/10.1016/j.wear.2013.12.030</a>","ama":"Frölich D, Magyar B, Sauer B. A comprehensive model of wear, friction and contact temperature in radial shaft seals. <i>Wear</i>. 2014;311(1):71-80. doi:<a href=\"https://doi.org/10.1016/j.wear.2013.12.030\">https://doi.org/10.1016/j.wear.2013.12.030</a>","ieee":"D. Frölich, B. Magyar, and B. Sauer, “A comprehensive model of wear, friction and contact temperature in radial shaft seals,” <i>Wear</i>, vol. 311, no. 1, pp. 71–80, 2014, doi: <a href=\"https://doi.org/10.1016/j.wear.2013.12.030\">https://doi.org/10.1016/j.wear.2013.12.030</a>.","chicago":"Frölich, D., Balázs Magyar, and B. Sauer. “A Comprehensive Model of Wear, Friction and Contact Temperature in Radial Shaft Seals.” <i>Wear</i> 311, no. 1 (2014): 71–80. <a href=\"https://doi.org/10.1016/j.wear.2013.12.030\">https://doi.org/10.1016/j.wear.2013.12.030</a>."},"intvolume":"       311","page":"71-80","publication_identifier":{"issn":["0043-1648"]},"issue":"1","keyword":["Radial shaft seal ring","Contact temperature","Wear","Friction torque","Finite element simulation"],"language":[{"iso":"eng"}],"extern":"1","_id":"34442","user_id":"38077","department":[{"_id":"146"}],"abstract":[{"text":"Radial shaft seals are used in a variety of applications, where rotating shafts in steady housings have to be sealed. Typical examples are crankshafts, camshafts, differential gear or hydraulic pumps. In the operating state the elastomeric seal ring and the shaft are separated by a lubrication film of just a few micrometers. Due to shear strain and fluid friction the contact area is subject to a higher temperature than the rest of the seal ring. The stiffness of the elastomeric material is intensely influenced by this temperature and thus contact pressure, friction and wear also strongly depend on the contact temperature. In order to simulate the contact behavior of elastomer seal rings it is essential to use a comprehensive approach which takes into consideration the interaction of temperature, friction and wear. Based on this idea a macroscopic simulation model has been developed at the MEGT. It combines a finite element approach for the simulation of contact pressure at different wear states, a semi-analytical approach for the calculation of contact temperature and an empirical approach for the calculation of friction. In this paper the model setup is presented, as well as simulation and experimental results.","lang":"eng"}],"status":"public","type":"journal_article","publication":"Wear"},{"citation":{"mla":"Althoff, Simon, et al. “A Friction Based Approach for Modeling Wire Bonding.” <i>IMAPS 2013, 46th International Symposium on Microelectronics</i>, 2013, doi:<a href=\"https://doi.org/10.4071/isom-2013-TA67\">10.4071/isom-2013-TA67</a>.","bibtex":"@inproceedings{Althoff_Neuhaus_Hemsel_Sextro_2013, place={Orlando (Florida), USA}, title={A friction based approach for modeling wire bonding}, DOI={<a href=\"https://doi.org/10.4071/isom-2013-TA67\">10.4071/isom-2013-TA67</a>}, booktitle={IMAPS 2013, 46th International Symposium on Microelectronics}, author={Althoff, Simon and Neuhaus, Jan and Hemsel, Tobias and Sextro, Walter}, year={2013} }","short":"S. Althoff, J. Neuhaus, T. Hemsel, W. Sextro, in: IMAPS 2013, 46th International Symposium on Microelectronics, Orlando (Florida), USA, 2013.","apa":"Althoff, S., Neuhaus, J., Hemsel, T., &#38; Sextro, W. (2013). A friction based approach for modeling wire bonding. In <i>IMAPS 2013, 46th International Symposium on Microelectronics</i>. Orlando (Florida), USA. <a href=\"https://doi.org/10.4071/isom-2013-TA67\">https://doi.org/10.4071/isom-2013-TA67</a>","ama":"Althoff S, Neuhaus J, Hemsel T, Sextro W. A friction based approach for modeling wire bonding. In: <i>IMAPS 2013, 46th International Symposium on Microelectronics</i>. Orlando (Florida), USA; 2013. doi:<a href=\"https://doi.org/10.4071/isom-2013-TA67\">10.4071/isom-2013-TA67</a>","chicago":"Althoff, Simon, Jan Neuhaus, Tobias Hemsel, and Walter Sextro. “A Friction Based Approach for Modeling Wire Bonding.” In <i>IMAPS 2013, 46th International Symposium on Microelectronics</i>. Orlando (Florida), USA, 2013. <a href=\"https://doi.org/10.4071/isom-2013-TA67\">https://doi.org/10.4071/isom-2013-TA67</a>.","ieee":"S. Althoff, J. Neuhaus, T. Hemsel, and W. Sextro, “A friction based approach for modeling wire bonding,” in <i>IMAPS 2013, 46th International Symposium on Microelectronics</i>, 2013."},"place":"Orlando (Florida), USA","year":"2013","date_created":"2019-05-13T13:55:36Z","author":[{"first_name":"Simon","full_name":"Althoff, Simon","last_name":"Althoff"},{"first_name":"Jan","full_name":"Neuhaus, Jan","last_name":"Neuhaus"},{"first_name":"Tobias","full_name":"Hemsel, Tobias","id":"210","last_name":"Hemsel"},{"last_name":"Sextro","full_name":"Sextro, Walter","id":"21220","first_name":"Walter"}],"date_updated":"2022-01-06T07:04:20Z","doi":"10.4071/isom-2013-TA67","title":"A friction based approach for modeling wire bonding","publication":"IMAPS 2013, 46th International Symposium on Microelectronics","type":"conference","status":"public","abstract":[{"text":"A model approach for wedge/wedge bonding copper wire is presented. The connection between wire and substrate is based on a variety of physical effects, but the dominant one is the friction based welding while applying ultrasound. Consequently, a friction model was used to investigate the welding process. This model is built up universal and can be used to describe the formation of micro welds in the time variant contact area between wire and substrate. Aim of the model is to identify the interactions between touchdown, bond normal force, ultrasonic power and bonding time. To do so, the contact area is discretized into partial areas where a Point Contact Model is applied. Based on this approach it is possible to simulate micro and macro slip inside the contact area between wire and substrate. The work done by friction force is a main criterion to define occurring micro joints which influence the subsequent welding.","lang":"eng"}],"department":[{"_id":"151"}],"user_id":"55222","_id":"9797","language":[{"iso":"eng"}],"keyword":["Wire bonding","friction modeling","wire bond quality","contact element modeling"]},{"citation":{"ama":"Hunstig M, Hemsel T, Sextro W. Modelling the friction contact in an inertia motor. <i>Journal of Intelligent Material Systems and Structures</i>. 2013;24(11):1380-1391. doi:<a href=\"https://doi.org/10.1177/1045389X12474354\">10.1177/1045389X12474354</a>","ieee":"M. Hunstig, T. Hemsel, and W. Sextro, “Modelling the friction contact in an inertia motor,” <i>Journal of Intelligent Material Systems and Structures</i>, vol. 24, no. 11, pp. 1380–1391, 2013.","chicago":"Hunstig, Matthias, Tobias Hemsel, and Walter Sextro. “Modelling the Friction Contact in an Inertia Motor.” <i>Journal of Intelligent Material Systems and Structures</i> 24, no. 11 (2013): 1380–91. <a href=\"https://doi.org/10.1177/1045389X12474354\">https://doi.org/10.1177/1045389X12474354</a>.","apa":"Hunstig, M., Hemsel, T., &#38; Sextro, W. (2013). Modelling the friction contact in an inertia motor. <i>Journal of Intelligent Material Systems and Structures</i>, <i>24</i>(11), 1380–1391. <a href=\"https://doi.org/10.1177/1045389X12474354\">https://doi.org/10.1177/1045389X12474354</a>","bibtex":"@article{Hunstig_Hemsel_Sextro_2013, title={Modelling the friction contact in an inertia motor}, volume={24}, DOI={<a href=\"https://doi.org/10.1177/1045389X12474354\">10.1177/1045389X12474354</a>}, number={11}, journal={Journal of Intelligent Material Systems and Structures}, author={Hunstig, Matthias and Hemsel, Tobias and Sextro, Walter}, year={2013}, pages={1380–1391} }","mla":"Hunstig, Matthias, et al. “Modelling the Friction Contact in an Inertia Motor.” <i>Journal of Intelligent Material Systems and Structures</i>, vol. 24, no. 11, 2013, pp. 1380–91, doi:<a href=\"https://doi.org/10.1177/1045389X12474354\">10.1177/1045389X12474354</a>.","short":"M. Hunstig, T. Hemsel, W. Sextro, Journal of Intelligent Material Systems and Structures 24 (2013) 1380–1391."},"page":"1380-1391","intvolume":"        24","year":"2013","issue":"11","doi":"10.1177/1045389X12474354","title":"Modelling the friction contact in an inertia motor","date_created":"2019-05-13T14:08:01Z","author":[{"full_name":"Hunstig, Matthias","last_name":"Hunstig","first_name":"Matthias"},{"id":"210","full_name":"Hemsel, Tobias","last_name":"Hemsel","first_name":"Tobias"},{"first_name":"Walter","last_name":"Sextro","full_name":"Sextro, Walter","id":"21220"}],"volume":24,"date_updated":"2022-01-06T07:04:21Z","status":"public","abstract":[{"text":"Piezoelectric inertia motors, also known as stickslip drives or (smooth) impact drives, use the inertia of a body to drive it by a friction contact in small steps, in the majority of motors composed of a stick phase and a slip phase between the friction partners. For optimizing inertia motors, it is important to understand the friction contact correctly and to measure its properties appropriately. This contribution presents experimental set-ups for measuring the contact force, friction force and relative displacement in an actual inertia motor with a dry friction contact and numerical simulations of the motor operation. The motor uses a pre-stressed multilayer actuator with a displacement in the range of 20 $\\mu$ m. It is shown that a previously postulated condition for the applicability of simple kinetic friction models is well fulfilled for the investigated motor. The friction contact in the motor is simulated using different kinetic friction models. The input for the friction models is the measured motion of the rod. The models qualitatively reproduce the measured motion but show quantitative deviations varying with frequency. These can be explained by vibrations of the driving rod that are experimentally investigated.","lang":"eng"}],"type":"journal_article","publication":"Journal of Intelligent Material Systems and Structures","language":[{"iso":"eng"}],"keyword":["Actuator","friction","motor","piezoelectric"],"user_id":"55222","department":[{"_id":"151"}],"_id":"9803"},{"date_updated":"2022-01-06T07:04:20Z","date_created":"2019-05-13T13:20:17Z","author":[{"last_name":"Hunstig","full_name":"Hunstig, Matthias","first_name":"Matthias"},{"full_name":"Hemsel, Tobias","last_name":"Hemsel","first_name":"Tobias"},{"first_name":"Walter","full_name":"Sextro, Walter","last_name":"Sextro"}],"title":"An efficient simulation technique for high-frequency piezoelectric inertia motors","doi":"10.1109/ULTSYM.2012.0068","publication_identifier":{"issn":["1948-5719"]},"quality_controlled":"1","year":"2012","page":"277-280","citation":{"short":"M. Hunstig, T. Hemsel, W. Sextro, in: Ultrasonics Symposium (IUS), 2012 IEEE International, 2012, pp. 277–280.","mla":"Hunstig, Matthias, et al. “An Efficient Simulation Technique for High-Frequency Piezoelectric Inertia Motors.” <i>Ultrasonics Symposium (IUS), 2012 IEEE International</i>, 2012, pp. 277–80, doi:<a href=\"https://doi.org/10.1109/ULTSYM.2012.0068\">10.1109/ULTSYM.2012.0068</a>.","bibtex":"@inproceedings{Hunstig_Hemsel_Sextro_2012, title={An efficient simulation technique for high-frequency piezoelectric inertia motors}, DOI={<a href=\"https://doi.org/10.1109/ULTSYM.2012.0068\">10.1109/ULTSYM.2012.0068</a>}, booktitle={Ultrasonics Symposium (IUS), 2012 IEEE International}, author={Hunstig, Matthias and Hemsel, Tobias and Sextro, Walter}, year={2012}, pages={277–280} }","apa":"Hunstig, M., Hemsel, T., &#38; Sextro, W. (2012). An efficient simulation technique for high-frequency piezoelectric inertia motors. In <i>Ultrasonics Symposium (IUS), 2012 IEEE International</i> (pp. 277–280). <a href=\"https://doi.org/10.1109/ULTSYM.2012.0068\">https://doi.org/10.1109/ULTSYM.2012.0068</a>","chicago":"Hunstig, Matthias, Tobias Hemsel, and Walter Sextro. “An Efficient Simulation Technique for High-Frequency Piezoelectric Inertia Motors.” In <i>Ultrasonics Symposium (IUS), 2012 IEEE International</i>, 277–80, 2012. <a href=\"https://doi.org/10.1109/ULTSYM.2012.0068\">https://doi.org/10.1109/ULTSYM.2012.0068</a>.","ieee":"M. Hunstig, T. Hemsel, and W. Sextro, “An efficient simulation technique for high-frequency piezoelectric inertia motors,” in <i>Ultrasonics Symposium (IUS), 2012 IEEE International</i>, 2012, pp. 277–280.","ama":"Hunstig M, Hemsel T, Sextro W. An efficient simulation technique for high-frequency piezoelectric inertia motors. In: <i>Ultrasonics Symposium (IUS), 2012 IEEE International</i>. ; 2012:277-280. doi:<a href=\"https://doi.org/10.1109/ULTSYM.2012.0068\">10.1109/ULTSYM.2012.0068</a>"},"_id":"9784","department":[{"_id":"151"}],"user_id":"55222","keyword":["friction","ultrasonic motors","Coulomb friction model","efficient simulation technique","friction contact","high-frequency piezoelectric inertia motor","motor characteristics prediction","numerical simulation","slip-slip mode","stick-slip mode","time-step simulation","ultrasonic inertia motor","Acceleration","Acoustics","Actuators","Computational modeling","Friction","Numerical models","Steady-state"],"language":[{"iso":"eng"}],"publication":"Ultrasonics Symposium (IUS), 2012 IEEE International","type":"conference","abstract":[{"text":"Piezoelectric inertia motors use the inertia of a body to drive it by means of a friction contact in a series of small steps. These motors can operate in ``stick-slip'' or ``slip-slip'' mode, with the fundamental frequency of the driving signal ranging from several Hertz to more than 100 kHz. To predict the motor characteristics, a Coulomb friction model is sufficient in many cases, but numerical simulation requires microscopic time steps. This contribution proposes a much faster simulation technique using one evaluation per period of the excitation signal. The proposed technique produces results very close to those of timestep simulation for ultrasonics inertia motors and allows direct determination of the steady-state velocity of an inertia motor from the motion profile of the driving part. Thus it is a useful simulation technique which can be applied in both analysis and design of inertia motors, especially for parameter studies and optimisation.","lang":"eng"}],"status":"public"},{"keyword":["Wheel--rail contact","Rolling contact","Friction","Interfacial fluid","Lubrication","Surface roughness","Contact temperature"],"language":[{"iso":"eng"}],"abstract":[{"text":"A profound description of friction in wheel--rail contact plays an essential role for optimization of traction control strategies, as input quantity for railway simulations in general and for the estimation of wear and rolling contact fatigue. A multitude of wheel--rail contact models exists, however, traction--creepage curves obtained from measurements show quantitative and qualitative deviations. There are several phenomena which influence the traction--creepage characteristics: Mechanisms resulting from surface roughness, frictional heating or the presence of interfacial fluids can have a dominating influence on friction. In this paper, a new wheel--rail contact model, accounting for these influential parameters, will be presented. The presented model accounts for the interaction of an interfacial fluid model for combined boundary and mixed lubrication of rough surfaces with a wheel--rail contact model that additionally accounts for frictional heating. A quantitative comparison with measurements found in the literature is not conducted, since the exact conditions of the measurements are mostly unknown and parameters can easily be adjusted to fit the measurements. Emphasis is placed on the qualitative behavior of the model with respect to the measurements and good agreement is found. The dependence of the maximum traction coefficient on rolling velocity, surface roughness and normal load is studied under dry and water lubricated conditions.","lang":"eng"}],"publication":"Wear","title":"Friction in wheel--rail contact: A model comprising interfacial fluids, surface roughness and temperature","date_created":"2019-05-13T11:08:32Z","year":"2011","quality_controlled":"1","_id":"9772","department":[{"_id":"151"}],"user_id":"55222","status":"public","type":"journal_article","doi":"10.1016/j.wear.2010.10.025","date_updated":"2022-01-06T07:04:19Z","volume":271,"author":[{"first_name":"Christoph","full_name":"Tomberger, Christoph","last_name":"Tomberger"},{"first_name":"Peter","full_name":"Dietmaier, Peter","last_name":"Dietmaier"},{"first_name":"Walter","id":"21220","full_name":"Sextro, Walter","last_name":"Sextro"},{"first_name":"Klaus","last_name":"Six","full_name":"Six, Klaus"}],"page":"2 - 12","intvolume":"       271","citation":{"ieee":"C. Tomberger, P. Dietmaier, W. Sextro, and K. Six, “Friction in wheel--rail contact: A model comprising interfacial fluids, surface roughness and temperature,” <i>Wear</i>, vol. 271, pp. 2–12, 2011.","chicago":"Tomberger, Christoph, Peter Dietmaier, Walter Sextro, and Klaus Six. “Friction in Wheel--Rail Contact: A Model Comprising Interfacial Fluids, Surface Roughness and Temperature.” <i>Wear</i> 271 (2011): 2–12. <a href=\"https://doi.org/10.1016/j.wear.2010.10.025\">https://doi.org/10.1016/j.wear.2010.10.025</a>.","ama":"Tomberger C, Dietmaier P, Sextro W, Six K. Friction in wheel--rail contact: A model comprising interfacial fluids, surface roughness and temperature. <i>Wear</i>. 2011;271:2-12. doi:<a href=\"https://doi.org/10.1016/j.wear.2010.10.025\">10.1016/j.wear.2010.10.025</a>","apa":"Tomberger, C., Dietmaier, P., Sextro, W., &#38; Six, K. (2011). Friction in wheel--rail contact: A model comprising interfacial fluids, surface roughness and temperature. <i>Wear</i>, <i>271</i>, 2–12. <a href=\"https://doi.org/10.1016/j.wear.2010.10.025\">https://doi.org/10.1016/j.wear.2010.10.025</a>","mla":"Tomberger, Christoph, et al. “Friction in Wheel--Rail Contact: A Model Comprising Interfacial Fluids, Surface Roughness and Temperature.” <i>Wear</i>, vol. 271, 2011, pp. 2–12, doi:<a href=\"https://doi.org/10.1016/j.wear.2010.10.025\">10.1016/j.wear.2010.10.025</a>.","short":"C. Tomberger, P. Dietmaier, W. Sextro, K. Six, Wear 271 (2011) 2–12.","bibtex":"@article{Tomberger_Dietmaier_Sextro_Six_2011, title={Friction in wheel--rail contact: A model comprising interfacial fluids, surface roughness and temperature}, volume={271}, DOI={<a href=\"https://doi.org/10.1016/j.wear.2010.10.025\">10.1016/j.wear.2010.10.025</a>}, journal={Wear}, author={Tomberger, Christoph and Dietmaier, Peter and Sextro, Walter and Six, Klaus}, year={2011}, pages={2–12} }"},"publication_identifier":{"issn":["0043-1648"]}},{"issue":"GT2004-53310","intvolume":"         6","page":"257-267","citation":{"ama":"Götting F, Sextro W, Panning L, Popp K. Systematic mistuning of bladed disk assemblies with friction contacts. In: <i>Proceedings of ASME TURBO Expo, Power for Land, Sea, and Air</i>. Vol 6. ; 2004:257-267.","ieee":"F. Götting, W. Sextro, L. Panning, and K. Popp, “Systematic mistuning of bladed disk assemblies with friction contacts,” in <i>Proceedings of ASME TURBO Expo, Power for Land, Sea, and Air</i>, 2004, vol. 6, no. GT2004-53310, pp. 257–267.","chicago":"Götting, Florian, Walter Sextro, Lars Panning, and Karl Popp. “Systematic Mistuning of Bladed Disk Assemblies with Friction Contacts.” In <i>Proceedings of ASME TURBO Expo, Power for Land, Sea, and Air</i>, 6:257–67, 2004.","mla":"Götting, Florian, et al. “Systematic Mistuning of Bladed Disk Assemblies with Friction Contacts.” <i>Proceedings of ASME TURBO Expo, Power for Land, Sea, and Air</i>, vol. 6, no. GT2004-53310, 2004, pp. 257–67.","short":"F. Götting, W. Sextro, L. Panning, K. Popp, in: Proceedings of ASME TURBO Expo, Power for Land, Sea, and Air, 2004, pp. 257–267.","bibtex":"@inproceedings{Götting_Sextro_Panning_Popp_2004, title={Systematic mistuning of bladed disk assemblies with friction contacts}, volume={6}, number={GT2004-53310}, booktitle={Proceedings of ASME TURBO Expo, Power for Land, Sea, and Air}, author={Götting, Florian and Sextro, Walter and Panning, Lars and Popp, Karl}, year={2004}, pages={257–267} }","apa":"Götting, F., Sextro, W., Panning, L., &#38; Popp, K. (2004). Systematic mistuning of bladed disk assemblies with friction contacts. In <i>Proceedings of ASME TURBO Expo, Power for Land, Sea, and Air</i> (Vol. 6, pp. 257–267)."},"year":"2004","volume":6,"author":[{"full_name":"Götting, Florian","last_name":"Götting","first_name":"Florian"},{"first_name":"Walter","last_name":"Sextro","id":"21220","full_name":"Sextro, Walter"},{"full_name":"Panning, Lars","last_name":"Panning","first_name":"Lars"},{"first_name":"Karl","full_name":"Popp, Karl","last_name":"Popp"}],"date_created":"2019-04-15T12:07:32Z","date_updated":"2022-01-06T07:04:05Z","title":"Systematic mistuning of bladed disk assemblies with friction contacts","publication":"Proceedings of ASME TURBO Expo, Power for Land, Sea, and Air","type":"conference","status":"public","abstract":[{"lang":"eng","text":"In turbomachinery, friction contacts are widely used to reduce dynamic stresses in turbine blades in order to avoid expensive damages. As a result of energy dissipation in the friction contacts the blade vibration amplitudes are reduced. In case of so-called friction dampers, which are pressed on the platforms of the blades by centrifugal forces, the damping effect can be optimized by varying the damper mass. This optimization can be done by means of a simulation model applying the so-called component mode synthesis and the Harmonic Balance Method to reduce computation time. It is based on the modal description of each substructure. In a real turbine or compressor blading great differences in the magnitude of the individual blade amplitudes occur caused by unavoidable mistuning of all system parameters like contact parameters and natural frequencies of the blades. It may happen that most of the blades experience only small stresses whereas a few blades experience critical stresses. Therefore, it is necessary to consider mistuning for all system parameters to simulate the forced response of bladed disk assemblies with friction contacts. For a mistuned bladed disk the complete system has to be modeled to calculate the dynamic response. In practice, usually the standard deviations instead of the distributions of the system parameters are known. Therefore, Monte-Carlo simulations are necessary to calculate the forced response of the blades for given mean values and standard deviations of the system parameters. To reduce the computational time, an approximate method has been developed and extended for small and moderate standard deviations of the system parameters to calculate the distribution and the envelopes of the frequency response functions for statistically varying system parameters, in the following called statistical mistuning. The approximate method is based on a sensitivity analysis and the assumption of a Weibull distribution of the vibration amplitudes of the blades. Both, the approximate method and the assumption of a Weibull distribution of the vibration amplitudes are validated by Monte-Carlo simulations. By these investigations the influence of different arrangements of the system parameters for given mean values and standard deviations of the vibration amplitudes of the blades can be determined, too. For the present investigations only a small influence of the arrangement of blades with respect to their natural frequencies has been observed. On the other hand, an intentional mistuning of the damper masses and the natural frequencies of the blades in a systematic way, in the following called systematic mistuning, can be investigated to reduce the amplitudes of the system. The simulation results of a systematic mistuning has been validated by a test rig with a rotating bladed disk assembly with friction dampers. The investigations show a good agreement between the simulations and the measurements but only a slight decrease of the maximum amplitudes in case of a systematic mistuning. Copyright {\\copyright} 2004 by ASME"}],"department":[{"_id":"151"}],"user_id":"55222","_id":"8952","language":[{"iso":"eng"}],"keyword":["Friction","Disks"]},{"publication":"Ultrasonics Symposium, 2000 IEEE","type":"conference","status":"public","abstract":[{"lang":"eng","text":"Ultrasonic linear motors have now been investigated for several years. Their key features are high thrust forces related to their volume and good position-accuracy. This contribution consists of two main parts. In the first part we describe the state-of-the-art of linear piezoelectric motors. Characteristics like no-load velocity, maximum thrust force and other technical properties of commercially available devices will be reported as well as those of prototypes. In the second part we report an ongoing research and development project aiming at a linear piezoelectric motor, which is capable of surpassing some of the shortcomings of other piezoelectric motors"}],"department":[{"_id":"151"}],"user_id":"55222","_id":"8915","language":[{"iso":"eng"}],"keyword":["linear motors","ultrasonic motors","linear piezoelectric motor","maximum thrust force","no-load velocity","ultrasonic linear motor","Electromagnetic devices","Electromagnetic fields","Frequency","Friction","Gears","Materials science and technology","Piezoelectric materials","Research and development","Vibrations","Wheels"],"quality_controlled":"1","publication_identifier":{"issn":["1051-0117"]},"intvolume":"         1","page":"663-666 vol.1","citation":{"apa":"Hemsel, T., &#38; Wallaschek, J. (2000). State of the art and development trends of ultrasonic linear motors. In <i>Ultrasonics Symposium, 2000 IEEE</i> (Vol. 1, pp. 663–666 vol.1). <a href=\"https://doi.org/10.1109/ULTSYM.2000.922635\">https://doi.org/10.1109/ULTSYM.2000.922635</a>","mla":"Hemsel, Tobias, and Jörg Wallaschek. “State of the Art and Development Trends of Ultrasonic Linear Motors.” <i>Ultrasonics Symposium, 2000 IEEE</i>, vol. 1, 2000, pp. 663–66 vol.1, doi:<a href=\"https://doi.org/10.1109/ULTSYM.2000.922635\">10.1109/ULTSYM.2000.922635</a>.","bibtex":"@inproceedings{Hemsel_Wallaschek_2000, title={State of the art and development trends of ultrasonic linear motors}, volume={1}, DOI={<a href=\"https://doi.org/10.1109/ULTSYM.2000.922635\">10.1109/ULTSYM.2000.922635</a>}, booktitle={Ultrasonics Symposium, 2000 IEEE}, author={Hemsel, Tobias and Wallaschek, Jörg}, year={2000}, pages={663–666 vol.1} }","short":"T. Hemsel, J. Wallaschek, in: Ultrasonics Symposium, 2000 IEEE, 2000, pp. 663–666 vol.1.","ama":"Hemsel T, Wallaschek J. State of the art and development trends of ultrasonic linear motors. In: <i>Ultrasonics Symposium, 2000 IEEE</i>. Vol 1. ; 2000:663-666 vol.1. doi:<a href=\"https://doi.org/10.1109/ULTSYM.2000.922635\">10.1109/ULTSYM.2000.922635</a>","ieee":"T. Hemsel and J. Wallaschek, “State of the art and development trends of ultrasonic linear motors,” in <i>Ultrasonics Symposium, 2000 IEEE</i>, 2000, vol. 1, pp. 663–666 vol.1.","chicago":"Hemsel, Tobias, and Jörg Wallaschek. “State of the Art and Development Trends of Ultrasonic Linear Motors.” In <i>Ultrasonics Symposium, 2000 IEEE</i>, 1:663–66 vol.1, 2000. <a href=\"https://doi.org/10.1109/ULTSYM.2000.922635\">https://doi.org/10.1109/ULTSYM.2000.922635</a>."},"year":"2000","volume":1,"date_created":"2019-04-15T09:52:09Z","author":[{"first_name":"Tobias","last_name":"Hemsel","id":"210","full_name":"Hemsel, Tobias"},{"full_name":"Wallaschek, Jörg","last_name":"Wallaschek","first_name":"Jörg"}],"date_updated":"2022-01-06T07:04:05Z","doi":"10.1109/ULTSYM.2000.922635","title":"State of the art and development trends of ultrasonic linear motors"}]