Details
| Original language | English |
|---|---|
| Pages (from-to) | 565-574 |
| Number of pages | 10 |
| Journal | Welding in the world |
| Volume | 63 |
| Issue number | 2 |
| Early online date | 12 Dec 2018 |
| Publication status | Published - 8 Mar 2019 |
Abstract
The increasing use of hot-formed steels for structural components in lightweight construction requires solutions to create mounting points into the thin blank of high-strength steel. Compared to welding nuts, self-piercing nuts are often used due to advantages for the mechanical properties. The problems of setting these elements in hot-formed steels like 22MnB5 are high process forces and often limited undercuts, which are produced during the joining process. In this regard, the application of the self-piercing nut during the hot forming process of 22MnB5 is the focus of the investigation. The particular challenge is to find out the desired process parameter in a defined temperature window. Thus, the ductile austenitized 22MnB5 is exploited, while the local shape of the deformed blank in contact with the self-piercing nut is realized. A newly developed process enables insertion of the self-piercing nuts by different joining conditions. In order to evaluate the efficiency of the new process, various aspects are recorded. To achieve a successful hot forming process by a complete martensitic microstructure transformation, a minimum cooling rate of 27 K/s is provided. Furthermore, it has to be assured, that there is no thermal influence on the nut element, while the blank and the self-piercing nut are strongly heated. Otherwise, this can lead to a change in the strength class of the nut. For this purpose, hardness measurement is used to analyze the microstructure development. The mechanical behavior is described by torsion- and pull-out tests.
Keywords
- 22MnB5, Hot forming, Mechanical joining, Self-piercing nuts
ASJC Scopus subject areas
- Engineering(all)
- Mechanics of Materials
- Engineering(all)
- Mechanical Engineering
- Materials Science(all)
- Metals and Alloys
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In: Welding in the world, Vol. 63, No. 2, 08.03.2019, p. 565-574.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Application of self-piercing nuts during hot forming of 22MNB5
AU - Meyer, Sebastian
AU - Meschut, Gerson
AU - Vogt, Hendrik
AU - Behrens, Bernd Arno
AU - Hübner, Sven
AU - Neumann, André
PY - 2019/3/8
Y1 - 2019/3/8
N2 - The increasing use of hot-formed steels for structural components in lightweight construction requires solutions to create mounting points into the thin blank of high-strength steel. Compared to welding nuts, self-piercing nuts are often used due to advantages for the mechanical properties. The problems of setting these elements in hot-formed steels like 22MnB5 are high process forces and often limited undercuts, which are produced during the joining process. In this regard, the application of the self-piercing nut during the hot forming process of 22MnB5 is the focus of the investigation. The particular challenge is to find out the desired process parameter in a defined temperature window. Thus, the ductile austenitized 22MnB5 is exploited, while the local shape of the deformed blank in contact with the self-piercing nut is realized. A newly developed process enables insertion of the self-piercing nuts by different joining conditions. In order to evaluate the efficiency of the new process, various aspects are recorded. To achieve a successful hot forming process by a complete martensitic microstructure transformation, a minimum cooling rate of 27 K/s is provided. Furthermore, it has to be assured, that there is no thermal influence on the nut element, while the blank and the self-piercing nut are strongly heated. Otherwise, this can lead to a change in the strength class of the nut. For this purpose, hardness measurement is used to analyze the microstructure development. The mechanical behavior is described by torsion- and pull-out tests.
AB - The increasing use of hot-formed steels for structural components in lightweight construction requires solutions to create mounting points into the thin blank of high-strength steel. Compared to welding nuts, self-piercing nuts are often used due to advantages for the mechanical properties. The problems of setting these elements in hot-formed steels like 22MnB5 are high process forces and often limited undercuts, which are produced during the joining process. In this regard, the application of the self-piercing nut during the hot forming process of 22MnB5 is the focus of the investigation. The particular challenge is to find out the desired process parameter in a defined temperature window. Thus, the ductile austenitized 22MnB5 is exploited, while the local shape of the deformed blank in contact with the self-piercing nut is realized. A newly developed process enables insertion of the self-piercing nuts by different joining conditions. In order to evaluate the efficiency of the new process, various aspects are recorded. To achieve a successful hot forming process by a complete martensitic microstructure transformation, a minimum cooling rate of 27 K/s is provided. Furthermore, it has to be assured, that there is no thermal influence on the nut element, while the blank and the self-piercing nut are strongly heated. Otherwise, this can lead to a change in the strength class of the nut. For this purpose, hardness measurement is used to analyze the microstructure development. The mechanical behavior is described by torsion- and pull-out tests.
KW - 22MnB5
KW - Hot forming
KW - Mechanical joining
KW - Self-piercing nuts
UR - http://www.scopus.com/inward/record.url?scp=85063276634&partnerID=8YFLogxK
U2 - 10.1007/s40194-018-00688-8
DO - 10.1007/s40194-018-00688-8
M3 - Article
AN - SCOPUS:85063276634
VL - 63
SP - 565
EP - 574
JO - Welding in the world
JF - Welding in the world
SN - 0043-2288
IS - 2
ER -