[{"citation":{"mla":"Scheidemann, Claus, et al. <i>Bolted Langevin Transducers with Leadfree Piezoelectric Ceramics</i>. 2025.","ama":"Scheidemann C, Bornmann P, Littmann W, Hemsel T. Bolted Langevin transducers with leadfree piezoelectric ceramics. In: ; 2025.","bibtex":"@inproceedings{Scheidemann_Bornmann_Littmann_Hemsel_2025, title={Bolted Langevin transducers with leadfree piezoelectric ceramics}, author={Scheidemann, Claus and Bornmann, Peter and Littmann, Walter and Hemsel, Tobias}, year={2025} }","apa":"Scheidemann, C., Bornmann, P., Littmann, W., &#38; Hemsel, T. (2025). <i>Bolted Langevin transducers with leadfree piezoelectric ceramics</i>. International Workshop on Piezoelectric Materials and Applications in Actuators (IWPMA), Vilnius, Lithuania.","ieee":"C. Scheidemann, P. Bornmann, W. Littmann, and T. Hemsel, “Bolted Langevin transducers with leadfree piezoelectric ceramics,” presented at the International Workshop on Piezoelectric Materials and Applications in Actuators (IWPMA), Vilnius, Lithuania, 2025.","short":"C. Scheidemann, P. Bornmann, W. Littmann, T. Hemsel, in: 2025.","chicago":"Scheidemann, Claus, Peter Bornmann, Walter Littmann, and Tobias Hemsel. “Bolted Langevin Transducers with Leadfree Piezoelectric Ceramics,” 2025."},"file_date_updated":"2026-03-02T11:00:37Z","abstract":[{"text":"Lead-containing piezoelectric ceramics are still the base for today’s ultrasonic transducers used in broad applications. This is partly due to missing powerful lead-free piezoelectric ceramic parts in the commercial market. There has been much research on lead-free materials but developing them into marketable parts seems to be an ongoing process. The actual exemption of ROHS has expired, but as the new exemption has already been requested, ceramic suppliers keep on selling lead containing products. Nevertheless, these should be replaced by lead-free alternatives for environmental and health issues. \r\nThis contribution focuses on exploring the technological readiness level of lead-free hard piezoceramics for prestressed ultrasonic transducers. A small series of bolted Langevin transducers was set up with standard PZT material and three commercial lead-free variants. Results of the building process from individual ring ceramic characteristics to transducer load tests are presented. The main finding of this study is that the lead-free materials technically can compete with the standard PZT for medium-power applications. Some adaptations in the ultrasonic system must be done: the geometry must be altered to fit resonance frequency, and higher voltages or thinner ceramics are needed to achieve the same vibration level at low load. For reaching same power, the volume of lead-free ceramics must be 1.5 to 3 times larger. As already promoted in literature, mechanical losses at high vibration levels are smaller for the lead-free materials. This might help to argument lead-free piezoelectric materials in some applications.\r\n\r\nReferences\r\n1.\tDirective 2011/65/EU of the European Parliament and of the Council of 8 June 2011 on the Restriction of the Use of Certain Hazardous Substances in Electrical and Electronic Equipment. EUR-Lex Document 02011L0065-20240801. Available online: http://data.europa.eu/eli/dir/2011/65/2024-08-01 (accessed on 24 January 2025).\r\n2.\tLangevin, P. (1918) Method and Apparatus for Transmitting and Receiving Submarine Elastic Waves Using the Piezoelectric Properties of Quartz. French Patent Office; Patent No. FR505703.\r\n3.\tHemsel, T.; Twiefel, J. (2023) Piezoelectric Ultrasonic Power Transducers. In Encyclopedia of Materials: Electronics; Academic Press: Oxford, UK; pp. 276–285. https://doi.org/10.1016/b978-0-12-819728-8.00047-4.\r\n4.\tATHENA Technologie Beratung GmbH (2025) Description of Ultrasound Generator. Available online: http://shop.myathena.de/epages/12074748.sf/de_DE/?ObjectPath=/Shops/12074748/Products/AM200 (accessed on 13 January 2025).\r\n5.\tLittmann, W.; Hemsel, T.; Kauczor, C.; Wallaschek, J.; Sinha, W. (2003) Load-adaptive phase-controller for resonant driven piezoelectric devices. Proc. World Congr. Ultrason. 2003, 48, 547–550.\r\n6.\tScheidemann, C., Bornmann, P., Littmann, W., & Hemsel, T. (2025). Lead-Free Ceramics in Prestressed Ultrasonic Transducers. Actuators, 14(2), 55. https://doi.org/10.3390/act14020055\r\n","lang":"eng"}],"date_created":"2026-03-02T10:39:40Z","file":[{"content_type":"application/pdf","file_id":"64799","date_updated":"2026-03-02T11:00:37Z","relation":"main_file","file_size":1812289,"access_level":"open_access","file_name":"IWPMA_2025_Hemsel.pdf","date_created":"2026-03-02T10:37:46Z","creator":"hemsel"}],"oa":"1","department":[{"_id":"151"}],"type":"conference","keyword":["lead free piezoelectric ceramics","bolted Langevin transducer","medium power ultrasound."],"conference":{"name":"International Workshop on Piezoelectric Materials and Applications in Actuators (IWPMA)","start_date":"2025-07-01","location":"Vilnius, Lithuania","end_date":"2025-07-03"},"author":[{"full_name":"Scheidemann, Claus","first_name":"Claus","last_name":"Scheidemann","id":"38259"},{"first_name":"Peter","last_name":"Bornmann","full_name":"Bornmann, Peter"},{"full_name":"Littmann, Walter","last_name":"Littmann","first_name":"Walter"},{"full_name":"Hemsel, Tobias","last_name":"Hemsel","first_name":"Tobias","id":"210"}],"status":"public","year":"2025","title":"Bolted Langevin transducers with leadfree piezoelectric ceramics","has_accepted_license":"1","date_updated":"2026-03-02T11:04:56Z","language":[{"iso":"eng"}],"_id":"64798","ddc":["620"],"user_id":"210"},{"quality_controlled":"1","citation":{"mla":"Hemsel, Tobias, and Jens Twiefel. “Piezoelectric Ultrasonic Power Transducers.” <i>Reference Module in Materials Science and Materials Engineering</i>, Elsevier, 2022, doi:<a href=\"https://doi.org/10.1016/b978-0-12-819728-8.00047-4\">10.1016/b978-0-12-819728-8.00047-4</a>.","ama":"Hemsel T, Twiefel J. Piezoelectric Ultrasonic Power Transducers. In: <i>Reference Module in Materials Science and Materials Engineering</i>. Elsevier; 2022. doi:<a href=\"https://doi.org/10.1016/b978-0-12-819728-8.00047-4\">10.1016/b978-0-12-819728-8.00047-4</a>","bibtex":"@inbook{Hemsel_Twiefel_2022, title={Piezoelectric Ultrasonic Power Transducers}, DOI={<a href=\"https://doi.org/10.1016/b978-0-12-819728-8.00047-4\">10.1016/b978-0-12-819728-8.00047-4</a>}, booktitle={Reference Module in Materials Science and Materials Engineering}, publisher={Elsevier}, author={Hemsel, Tobias and Twiefel, Jens}, year={2022} }","apa":"Hemsel, T., &#38; Twiefel, J. (2022). Piezoelectric Ultrasonic Power Transducers. In <i>Reference Module in Materials Science and Materials Engineering</i>. Elsevier. <a href=\"https://doi.org/10.1016/b978-0-12-819728-8.00047-4\">https://doi.org/10.1016/b978-0-12-819728-8.00047-4</a>","ieee":"T. Hemsel and J. Twiefel, “Piezoelectric Ultrasonic Power Transducers,” in <i>Reference Module in Materials Science and Materials Engineering</i>, Elsevier, 2022.","short":"T. Hemsel, J. Twiefel, in: Reference Module in Materials Science and Materials Engineering, Elsevier, 2022.","chicago":"Hemsel, Tobias, and Jens Twiefel. “Piezoelectric Ultrasonic Power Transducers.” In <i>Reference Module in Materials Science and Materials Engineering</i>. Elsevier, 2022. <a href=\"https://doi.org/10.1016/b978-0-12-819728-8.00047-4\">https://doi.org/10.1016/b978-0-12-819728-8.00047-4</a>."},"user_id":"210","_id":"33500","publisher":"Elsevier","status":"public","department":[{"_id":"151"}],"type":"book_chapter","keyword":["Equivalent circuit model","Langevin transducer","Lumped parameter model","Piezoelectric transducer","Ultrasonic processes","Ultrasound"],"date_created":"2022-09-30T09:35:16Z","abstract":[{"text":"This article is dedicated to piezoelectric ultrasonic power transducers that differ to well known medical ultrasonic diagnostic apparatus or non destructive testing devices by the level of power in use; typically several tens of up to more than thousand watts are used in a multitude of different applications. After a short introduction including historical development, the first focus is on theoretical background of the operating principle, design and mechanical modeling. As piezoelectric elements transform electrical to mechanical energy and vice versa, equivalent circuit modeling is also described. After that, sample applications are delineated by the matter wherein ultrasound generates unique effects: incredible high pressure level as well in air as in water, micro-bubbles generating temperature peaks for very short time instances in fluids, acoustoplastic effect, enhancement of diffusion and recrystallization in solids, friction manipulation, incremental deformation and micro-cracking of surfaces, or even generation of macroscopic movements in motors. At the end, some future directions ranging from novel modeling approaches to advanced control and new materials are addressed.","lang":"eng"}],"publication":"Reference Module in Materials Science and Materials Engineering","doi":"10.1016/b978-0-12-819728-8.00047-4","language":[{"iso":"eng"}],"main_file_link":[{"url":"https://www.sciencedirect.com/science/article/pii/B9780128197288000474"}],"date_updated":"2022-09-30T09:41:47Z","publication_status":"published","publication_identifier":{"isbn":["978-0-12-803581-8"]},"author":[{"first_name":"Tobias","last_name":"Hemsel","full_name":"Hemsel, Tobias","id":"210"},{"first_name":"Jens","last_name":"Twiefel","full_name":"Twiefel, Jens"}],"year":"2022","title":"Piezoelectric Ultrasonic Power Transducers"},{"language":[{"iso":"eng"}],"doi":"10.3938/jkps.57.929","title":"Modeling of Piezoelectric Langevin Transducers by Using Mixed Transfer Matrix Methods","year":"2010","author":[{"first_name":"Bo","last_name":"Fu","full_name":"Fu, Bo"},{"last_name":"Li","first_name":"Chao","full_name":"Li, Chao"},{"first_name":"Jianming","last_name":"Zhang","full_name":"Zhang, Jianming"},{"last_name":"Huang","first_name":"Zhenwei","full_name":"Huang, Zhenwei"},{"id":"210","full_name":"Hemsel, Tobias","first_name":"Tobias","last_name":"Hemsel"}],"publication_identifier":{"issn":["1948-5719"]},"date_updated":"2022-01-06T07:04:19Z","intvolume":"        57","date_created":"2019-05-13T09:40:42Z","keyword":["Piezoelectric langevin transducer","Transfer matrix method","Four (six)-pole element description","Pre-stressed bolt"],"type":"journal_article","department":[{"_id":"151"}],"issue":"4","publication":"Journal of Korean Physical Society","abstract":[{"text":"In the modeling of piezoelectric Langevin transducers using usual transfer matrix methods, some simplifications have been adopted. This leads to reduction of the model quality. A mixed transfer matrix method is employed in the modeling of Langevin transducers, where the pre-stressed bolt is modeled as a separate four-pole element, which is connected to other elements in parallel. Based on the mixed transfer matrix method, the four (six)-pole element description of the piezoelectric Langevin transducer is built up and the total transfer matrix relation is derived. The resonance frequencies of the transducer are calculated and then measured using the impedance analyzer (HP4192). Experimental result shows that the mixed transfer matrix method has better modeling quality than the usual transfer matrix method for the vibration analysis of piezoelectric Langevin transducers.","lang":"eng"}],"page":"929","_id":"9745","user_id":"55222","volume":57,"status":"public","citation":{"ieee":"B. Fu, C. Li, J. Zhang, Z. Huang, and T. Hemsel, “Modeling of Piezoelectric Langevin Transducers by Using Mixed Transfer Matrix Methods,” <i>Journal of Korean Physical Society</i>, vol. 57, no. 4, p. 929, 2010.","mla":"Fu, Bo, et al. “Modeling of Piezoelectric Langevin Transducers by Using Mixed Transfer Matrix Methods.” <i>Journal of Korean Physical Society</i>, vol. 57, no. 4, 2010, p. 929, doi:<a href=\"https://doi.org/10.3938/jkps.57.929\">10.3938/jkps.57.929</a>.","apa":"Fu, B., Li, C., Zhang, J., Huang, Z., &#38; Hemsel, T. (2010). Modeling of Piezoelectric Langevin Transducers by Using Mixed Transfer Matrix Methods. <i>Journal of Korean Physical Society</i>, <i>57</i>(4), 929. <a href=\"https://doi.org/10.3938/jkps.57.929\">https://doi.org/10.3938/jkps.57.929</a>","bibtex":"@article{Fu_Li_Zhang_Huang_Hemsel_2010, title={Modeling of Piezoelectric Langevin Transducers by Using Mixed Transfer Matrix Methods}, volume={57}, DOI={<a href=\"https://doi.org/10.3938/jkps.57.929\">10.3938/jkps.57.929</a>}, number={4}, journal={Journal of Korean Physical Society}, author={Fu, Bo and Li, Chao and Zhang, Jianming and Huang, Zhenwei and Hemsel, Tobias}, year={2010}, pages={929} }","chicago":"Fu, Bo, Chao Li, Jianming Zhang, Zhenwei Huang, and Tobias Hemsel. “Modeling of Piezoelectric Langevin Transducers by Using Mixed Transfer Matrix Methods.” <i>Journal of Korean Physical Society</i> 57, no. 4 (2010): 929. <a href=\"https://doi.org/10.3938/jkps.57.929\">https://doi.org/10.3938/jkps.57.929</a>.","short":"B. Fu, C. Li, J. Zhang, Z. Huang, T. Hemsel, Journal of Korean Physical Society 57 (2010) 929.","ama":"Fu B, Li C, Zhang J, Huang Z, Hemsel T. Modeling of Piezoelectric Langevin Transducers by Using Mixed Transfer Matrix Methods. <i>Journal of Korean Physical Society</i>. 2010;57(4):929. doi:<a href=\"https://doi.org/10.3938/jkps.57.929\">10.3938/jkps.57.929</a>"},"quality_controlled":"1"},{"quality_controlled":"1","citation":{"chicago":"Hemsel, Tobias, Ernst Günther Lierk, Walter Littmann, and Takeshi Morita. “Various Aspects of the Placement of a Piezoelectric Material in Composite Actuators, Motors, and Transducers.” <i>Journal of Korean Physical Society</i> 57, no. 4 (2010): 933–37. <a href=\"https://doi.org/10.3938/jkps.57.933\">https://doi.org/10.3938/jkps.57.933</a>.","short":"T. Hemsel, E.G. Lierk, W. Littmann, T. Morita, Journal of Korean Physical Society 57 (2010) 933–937.","ieee":"T. Hemsel, E. G. Lierk, W. Littmann, and T. Morita, “Various Aspects of the Placement of a Piezoelectric Material in Composite Actuators, Motors, and Transducers,” <i>Journal of Korean Physical Society</i>, vol. 57, no. 4, pp. 933–937, 2010.","apa":"Hemsel, T., Lierk, E. G., Littmann, W., &#38; Morita, T. (2010). Various Aspects of the Placement of a Piezoelectric Material in Composite Actuators, Motors, and Transducers. <i>Journal of Korean Physical Society</i>, <i>57</i>(4), 933–937. <a href=\"https://doi.org/10.3938/jkps.57.933\">https://doi.org/10.3938/jkps.57.933</a>","bibtex":"@article{Hemsel_Lierk_Littmann_Morita_2010, title={Various Aspects of the Placement of a Piezoelectric Material in Composite Actuators, Motors, and Transducers}, volume={57}, DOI={<a href=\"https://doi.org/10.3938/jkps.57.933\">10.3938/jkps.57.933</a>}, number={4}, journal={Journal of Korean Physical Society}, author={Hemsel, Tobias and Lierk, Ernst Günther and Littmann, Walter and Morita, Takeshi}, year={2010}, pages={933–937} }","ama":"Hemsel T, Lierk EG, Littmann W, Morita T. Various Aspects of the Placement of a Piezoelectric Material in Composite Actuators, Motors, and Transducers. <i>Journal of Korean Physical Society</i>. 2010;57(4):933-937. doi:<a href=\"https://doi.org/10.3938/jkps.57.933\">10.3938/jkps.57.933</a>","mla":"Hemsel, Tobias, et al. “Various Aspects of the Placement of a Piezoelectric Material in Composite Actuators, Motors, and Transducers.” <i>Journal of Korean Physical Society</i>, vol. 57, no. 4, 2010, pp. 933–37, doi:<a href=\"https://doi.org/10.3938/jkps.57.933\">10.3938/jkps.57.933</a>."},"user_id":"55222","volume":57,"page":"933-937","_id":"9749","status":"public","keyword":["Bolted Langevin transducer","Optimum placement of piezoelectric ceramics"],"type":"journal_article","department":[{"_id":"151"}],"date_created":"2019-05-13T09:56:22Z","abstract":[{"lang":"eng","text":"Piezoelectric materials find wide application in technical systems. Most often, a combination of piezoelectric and other materials is advantageous. The position and the amount of the piezoelectric material within the overall system depends on various aspects like maximum mechanical output to the load, maximum electromechanical efficiency of the system, maximum utilization of the piezoelectric material, minimum self-heating of the piezoelectric material, and controllability of the system, which might be key aspects for the optimisation of the system design. For a composite longitudinal vibrator (bolted Langevin transducer), which is a base for many technical applications, this contribution shows in detail, how above mentioned aspects depend on the position and volume of the piezoelectric material related to the mode shape."}],"issue":"4","publication":"Journal of Korean Physical Society","doi":"10.3938/jkps.57.933","language":[{"iso":"eng"}],"date_updated":"2022-01-06T07:04:19Z","intvolume":"        57","year":"2010","title":"Various Aspects of the Placement of a Piezoelectric Material in Composite Actuators, Motors, and Transducers","author":[{"id":"210","first_name":"Tobias","last_name":"Hemsel","full_name":"Hemsel, Tobias"},{"first_name":"Ernst Günther","last_name":"Lierk","full_name":"Lierk, Ernst Günther"},{"full_name":"Littmann, Walter","first_name":"Walter","last_name":"Littmann"},{"full_name":"Morita, Takeshi","last_name":"Morita","first_name":"Takeshi"}],"publication_identifier":{"issn":["1948-5719"]}},{"doi":"10.1109/SPAWDA.2008.4775801","user_id":"55222","page":"324-327","language":[{"iso":"eng"}],"_id":"9568","date_updated":"2022-01-06T07:04:16Z","title":"A simple pre-stress estimating method of langevin transducers","year":"2008","status":"public","author":[{"full_name":"Bo, Fu","first_name":"Fu","last_name":"Bo"},{"full_name":"Ting, Li","last_name":"Ting","first_name":"Li"},{"id":"210","full_name":"Hemsel, Tobias","last_name":"Hemsel","first_name":"Tobias"}],"type":"conference","keyword":["capacitors","impedance convertors","piezoelectric transducers","stress analysis","Langevin transducers","basic circuit theory","capacitor","impedance converter","piezoelectric equation","pre-stress estimating method","voltmeter","Capacitors","Educational institutions","Equations","Force measurement","Impedance measurement","Manufacturing","Mechatronics","Piezoelectric transducers","Voltage","Voltmeters","Langevin transducer","capacitor","piezoelectric element","pre-stress"],"department":[{"_id":"151"}],"date_created":"2019-04-29T11:16:13Z","abstract":[{"text":"A simple pre-stress estimate method of Langevin transducers is studied. The measurement setup consists of a capacitor, an impedance converter and a voltmeter. Based on the piezoelectric equation and the basic circuit theory, the mathematical expression between the pre-stress and the voltage across the capacitor is derived. The pre-stress level can then be calculated out of the measurement of the capacitor voltage. In order to evaluate the precision of this method, a force washer is used to measure the pre-stress of the Langevin transducer. The result shows the pre-stress level obtained from this method is 30-40\\% higher than the pre-stress level measured by the force washer. This method is simple and can be used to estimate the pre-stress of various Langevin transducers. The precision of this method can be raised if d33 is identified under different pre-stress levels.","lang":"eng"}],"publication":"Piezoelectricity, Acoustic Waves, and Device Applications, 2008. SPAWDA 2008. Symposium on","citation":{"ieee":"F. Bo, L. Ting, and T. Hemsel, “A simple pre-stress estimating method of langevin transducers,” in <i>Piezoelectricity, Acoustic Waves, and Device Applications, 2008. SPAWDA 2008. Symposium on</i>, 2008, pp. 324–327.","apa":"Bo, F., Ting, L., &#38; Hemsel, T. (2008). A simple pre-stress estimating method of langevin transducers. In <i>Piezoelectricity, Acoustic Waves, and Device Applications, 2008. SPAWDA 2008. Symposium on</i> (pp. 324–327). <a href=\"https://doi.org/10.1109/SPAWDA.2008.4775801\">https://doi.org/10.1109/SPAWDA.2008.4775801</a>","mla":"Bo, Fu, et al. “A Simple Pre-Stress Estimating Method of Langevin Transducers.” <i>Piezoelectricity, Acoustic Waves, and Device Applications, 2008. SPAWDA 2008. Symposium On</i>, 2008, pp. 324–27, doi:<a href=\"https://doi.org/10.1109/SPAWDA.2008.4775801\">10.1109/SPAWDA.2008.4775801</a>.","bibtex":"@inproceedings{Bo_Ting_Hemsel_2008, title={A simple pre-stress estimating method of langevin transducers}, DOI={<a href=\"https://doi.org/10.1109/SPAWDA.2008.4775801\">10.1109/SPAWDA.2008.4775801</a>}, booktitle={Piezoelectricity, Acoustic Waves, and Device Applications, 2008. SPAWDA 2008. Symposium on}, author={Bo, Fu and Ting, Li and Hemsel, Tobias}, year={2008}, pages={324–327} }","chicago":"Bo, Fu, Li Ting, and Tobias Hemsel. “A Simple Pre-Stress Estimating Method of Langevin Transducers.” In <i>Piezoelectricity, Acoustic Waves, and Device Applications, 2008. SPAWDA 2008. Symposium On</i>, 324–27, 2008. <a href=\"https://doi.org/10.1109/SPAWDA.2008.4775801\">https://doi.org/10.1109/SPAWDA.2008.4775801</a>.","short":"F. Bo, L. Ting, T. Hemsel, in: Piezoelectricity, Acoustic Waves, and Device Applications, 2008. SPAWDA 2008. Symposium On, 2008, pp. 324–327.","ama":"Bo F, Ting L, Hemsel T. A simple pre-stress estimating method of langevin transducers. In: <i>Piezoelectricity, Acoustic Waves, and Device Applications, 2008. SPAWDA 2008. Symposium On</i>. ; 2008:324-327. doi:<a href=\"https://doi.org/10.1109/SPAWDA.2008.4775801\">10.1109/SPAWDA.2008.4775801</a>"}}]