---
_id: '19976'
abstract:
- lang: eng
text: The aim to reduce pollutant emission has led to a trend towards lightweight
construction in car body development during the last years. As a consequence of
the resulting need for multi-material design, mechanical joining technologies
become increasingly important. Mechanical joining allows for the combination of
dissimilar materials, while thermic joining techniques reach their limits. Self-piercing
riveting enables the joining of dissimilar materials by using semi-tubular rivets
as mechanical fasteners. The rivet production, however, is costly and time-consuming,
as the rivets generally have to be hardened, tempered and coated after forming,
in order to achieve an adequate strength and corrosion resistance. A promising
approach to improve the efficiency of the rivet manufacturing is the use of high-strength
high nitrogen steel as rivet material because these additional process steps would
not be necessary anymore. As a result of the comparatively high nitrogen content,
such steels have various beneficial properties like higher strength, good ductility
and improved corrosion resistance. By cold bulk forming of high nitrogen steels
high-strength parts can be manufactured due to the strengthening which is caused
by the high strain hardening. However, high tool loads thereby have to be expected
and are a major challenge during the production process. Consequently, there is
a need for appropriate forming strategies. This paper presents key aspects concerning
the process design for the manufacturing of semi-tubular self-piercing rivets
made of high-strength steel. The aim is to produce the rivets in several forming
stages without intermediate heat treatment between the single stages. Due to the
high strain hardening of the material, a two stage forming concept will be investigated.
Cup-backward extrusion is chosen as the first process step in order to form the
rivet shank without forming the rivet foot. Thus, the strain hardening effects
in the area of the rivet foot are minimized and the tool loads during the following
process step can be reduced. During the second and final forming stage the detailed
geometry of the rivet foot and the rivet head is formed. In this context, the
effect of different variations, for example concerning the final geometry of the
rivet foot, on the tool load is investigated using multistage numerical analysis.
Furthermore, the influence of the process temperature on occurring stresses is
analysed. Based on the results of the investigations, an adequate forming strategy
and a tool concept for the manufacturing of semi-tubular self-piercing rivets
made of high-strength steel are presented.
citation:
ama: Kuball C-M, Uhe B, Meschut G, Merklein M, eds. Process Design for the Forming
of Semi-Tubular Self-Piercing Rivets Made of High Nitrogen Steel. Vol 50.;
2020:280-285. doi:10.1016/j.promfg.2020.08.052
apa: Kuball, C.-M., Uhe, B., Meschut, G., & Merklein, M. (Eds.). (2020). Process
design for the forming of semi-tubular self-piercing rivets made of high nitrogen
steel (Vol. 50, pp. 280–285). https://doi.org/10.1016/j.promfg.2020.08.052
bibtex: '@book{Kuball_Uhe_Meschut_Merklein_2020, series={Procedia Manufacturing},
title={Process design for the forming of semi-tubular self-piercing rivets made
of high nitrogen steel}, volume={50}, DOI={10.1016/j.promfg.2020.08.052},
year={2020}, pages={280–285}, collection={Procedia Manufacturing} }'
chicago: Kuball, Clara-Maria, Benedikt Uhe, Gerson Meschut, and Marion Merklein,
eds. Process Design for the Forming of Semi-Tubular Self-Piercing Rivets Made
of High Nitrogen Steel. Vol. 50. Procedia Manufacturing, 2020. https://doi.org/10.1016/j.promfg.2020.08.052.
ieee: C.-M. Kuball, B. Uhe, G. Meschut, and M. Merklein, Eds., Process design
for the forming of semi-tubular self-piercing rivets made of high nitrogen steel,
vol. 50. 2020, pp. 280–285.
mla: Kuball, Clara-Maria, et al., editors. Process Design for the Forming of
Semi-Tubular Self-Piercing Rivets Made of High Nitrogen Steel. 2020, pp. 280–85,
doi:10.1016/j.promfg.2020.08.052.
short: C.-M. Kuball, B. Uhe, G. Meschut, M. Merklein, eds., Process Design for the
Forming of Semi-Tubular Self-Piercing Rivets Made of High Nitrogen Steel, 2020.
date_created: 2020-10-12T08:30:08Z
date_updated: 2026-02-27T10:43:48Z
department:
- _id: '157'
doi: 10.1016/j.promfg.2020.08.052
editor:
- first_name: Clara-Maria
full_name: Kuball, Clara-Maria
last_name: Kuball
- first_name: Benedikt
full_name: Uhe, Benedikt
id: '38131'
last_name: Uhe
- first_name: Gerson
full_name: Meschut, Gerson
id: '32056'
last_name: Meschut
orcid: 0000-0002-2763-1246
- first_name: Marion
full_name: Merklein, Marion
last_name: Merklein
intvolume: ' 50'
keyword:
- high nitrogen steel
- self-piercing riveting
- joining by forming
- bulk forming
- tool design
language:
- iso: eng
page: 280-285
publication_status: published
quality_controlled: '1'
series_title: Procedia Manufacturing
status: public
title: Process design for the forming of semi-tubular self-piercing rivets made of
high nitrogen steel
type: conference_editor
user_id: '53912'
volume: 50
year: '2020'
...
---
_id: '9992'
abstract:
- lang: eng
text: State-of-the-art industrial compact high power electronic packages require
copper-copper interconnections with larger cross sections made by ultrasonic bonding.
In comparison to aluminium-copper, copper-copper interconnections require increased
normal forces and ultrasonic power, which might lead to substrate damage due to
increased mechanical stresses. One option to raise friction energy without increasing
vibration amplitude between wire and substrate or bonding force is the use of
two-dimensional vibration. The first part of this contribution reports on the
development of a novel bonding system that executes two-dimensional vibrations
of a tool-tip to bond a nail- like pin onto a copper substrate. Since intermetallic
bonds only form properly when surfaces are clean, oxide free and activated, the
geometries of tool-tip and pin were optimised using finite element analysis. To
maximize the area of the bonded annulus the distribution of normal pressure was
optimized by varying the convexity of the bottom side of the pin. Second, a statistical
model obtained from an experimental parameter study shows the influence of different
bonding parameters on the bond result. To find bonding parameters with the minimum
number of tests, the experiments have been planned using a D-optimal experimental
design approach.
author:
- first_name: Collin
full_name: Dymel, Collin
id: '66833'
last_name: Dymel
- first_name: Paul
full_name: Eichwald, Paul
last_name: Eichwald
- first_name: Reinhard
full_name: Schemmel, Reinhard
id: '28647'
last_name: Schemmel
- first_name: Tobias
full_name: Hemsel, Tobias
id: '210'
last_name: Hemsel
- first_name: Michael
full_name: Brökelmann, Michael
last_name: Brökelmann
- first_name: Matthias
full_name: Hunstig, Matthias
last_name: Hunstig
- first_name: Walter
full_name: Sextro, Walter
id: '21220'
last_name: Sextro
citation:
ama: 'Dymel C, Eichwald P, Schemmel R, et al. Numerical and statistical investigation
of weld formation in a novel two-dimensional copper-copper bonding process. In:
(Proceedings of 7th Electronics System-Integration Technology Conference, Dresden,
Germany). ; 2018:1-6.'
apa: Dymel, C., Eichwald, P., Schemmel, R., Hemsel, T., Brökelmann, M., Hunstig,
M., & Sextro, W. (2018). Numerical and statistical investigation of weld formation
in a novel two-dimensional copper-copper bonding process. In (Proceedings of
7th Electronics System-Integration Technology Conference, Dresden, Germany)
(pp. 1–6).
bibtex: '@inproceedings{Dymel_Eichwald_Schemmel_Hemsel_Brökelmann_Hunstig_Sextro_2018,
title={Numerical and statistical investigation of weld formation in a novel two-dimensional
copper-copper bonding process}, booktitle={(Proceedings of 7th Electronics System-Integration
Technology Conference, Dresden, Germany)}, author={Dymel, Collin and Eichwald,
Paul and Schemmel, Reinhard and Hemsel, Tobias and Brökelmann, Michael and Hunstig,
Matthias and Sextro, Walter}, year={2018}, pages={1–6} }'
chicago: Dymel, Collin, Paul Eichwald, Reinhard Schemmel, Tobias Hemsel, Michael
Brökelmann, Matthias Hunstig, and Walter Sextro. “Numerical and Statistical Investigation
of Weld Formation in a Novel Two-Dimensional Copper-Copper Bonding Process.” In
(Proceedings of 7th Electronics System-Integration Technology Conference, Dresden,
Germany), 1–6, 2018.
ieee: C. Dymel et al., “Numerical and statistical investigation of weld formation
in a novel two-dimensional copper-copper bonding process,” in (Proceedings
of 7th Electronics System-Integration Technology Conference, Dresden, Germany),
2018, pp. 1–6.
mla: Dymel, Collin, et al. “Numerical and Statistical Investigation of Weld Formation
in a Novel Two-Dimensional Copper-Copper Bonding Process.” (Proceedings of
7th Electronics System-Integration Technology Conference, Dresden, Germany),
2018, pp. 1–6.
short: 'C. Dymel, P. Eichwald, R. Schemmel, T. Hemsel, M. Brökelmann, M. Hunstig,
W. Sextro, in: (Proceedings of 7th Electronics System-Integration Technology Conference,
Dresden, Germany), 2018, pp. 1–6.'
date_created: 2019-05-27T10:18:10Z
date_updated: 2020-05-07T05:33:56Z
department:
- _id: '151'
keyword:
- ultrasonic wire-bonding
- bond-tool design
- parameter identification
- statistical engineering
language:
- iso: eng
page: 1-6
project:
- _id: '93'
grant_number: MP-1-1-015
name: Hochleistungsbonden in energieeffizienten Leistungshalbleitermodulen
publication: (Proceedings of 7th Electronics System-Integration Technology Conference,
Dresden, Germany)
quality_controlled: '1'
status: public
title: Numerical and statistical investigation of weld formation in a novel two-dimensional
copper-copper bonding process
type: conference
user_id: '210'
year: '2018'
...