---
_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. <i>Process Design for the Forming
    of Semi-Tubular Self-Piercing Rivets Made of High Nitrogen Steel</i>. Vol 50.;
    2020:280-285. doi:<a href="https://doi.org/10.1016/j.promfg.2020.08.052">10.1016/j.promfg.2020.08.052</a>
  apa: Kuball, C.-M., Uhe, B., Meschut, G., &#38; Merklein, M. (Eds.). (2020). <i>Process
    design for the forming of semi-tubular self-piercing rivets made of high nitrogen
    steel</i> (Vol. 50, pp. 280–285). <a href="https://doi.org/10.1016/j.promfg.2020.08.052">https://doi.org/10.1016/j.promfg.2020.08.052</a>
  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={<a href="https://doi.org/10.1016/j.promfg.2020.08.052">10.1016/j.promfg.2020.08.052</a>},
    year={2020}, pages={280–285}, collection={Procedia Manufacturing} }'
  chicago: Kuball, Clara-Maria, Benedikt Uhe, Gerson Meschut, and Marion Merklein,
    eds. <i>Process Design for the Forming of Semi-Tubular Self-Piercing Rivets Made
    of High Nitrogen Steel</i>. Vol. 50. Procedia Manufacturing, 2020. <a href="https://doi.org/10.1016/j.promfg.2020.08.052">https://doi.org/10.1016/j.promfg.2020.08.052</a>.
  ieee: C.-M. Kuball, B. Uhe, G. Meschut, and M. Merklein, Eds., <i>Process design
    for the forming of semi-tubular self-piercing rivets made of high nitrogen steel</i>,
    vol. 50. 2020, pp. 280–285.
  mla: Kuball, Clara-Maria, et al., editors. <i>Process Design for the Forming of
    Semi-Tubular Self-Piercing Rivets Made of High Nitrogen Steel</i>. 2020, pp. 280–85,
    doi:<a href="https://doi.org/10.1016/j.promfg.2020.08.052">10.1016/j.promfg.2020.08.052</a>.
  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: '19974'
abstract:
- lang: eng
  text: Due to the trend towards lightweight design in car body development mechanical
    joining technologies become increasingly important. These techniques allow for
    the joining of dissimilar materials and thus enable multi-material design, while
    thermic joining methods reach their limits. Semi-tubular self-piercing riveting
    is an important mechanical joining technology. The rivet production, however,
    is costly and time-consuming, as the process consists of several process steps
    including the heat treatment and coating of the rivets in order to achieve an
    adequate strength and corrosion resistance. The use of high nitrogen steel as
    rivet material leads to the possibility of reducing process steps and hence increasing
    the efficiency of the process. However, the high tool loads being expected due
    to the high strain hardening of the material are a major challenge during the
    rivet production. Thus, there is a need for appropriate forming strategies, such
    as the manufacturing of the rivets at elevated temperatures. Prior investigations
    led to the conclusion that forming already at 200 °C results in a distinct reduction
    of the yield strength. To create a deeper understanding of the forming behaviour
    of high nitrogen steel at elevated temperatures, compression tests were conducted
    in a temperature range between room temperature and 200 °C. The determined true
    stress – true strain curves are the basis for the further process and tool design
    of the rivet production. Another key factor for the rivet manufacturing at elevated
    temperatures is the influence of the process temperature on the tribological conditions.
    For this reason, ring compression tests at room temperature and 200 °C are carried
    out. The friction factors are determined on the basis of calibration curves resulting
    from the numerical analysis of the ring compression process. The investigations
    indicate that the friction factor at 200 °C is significantly higher compared to
    room temperature. This essential fact has to be taken into account for the process
    and tool design for the rivet production using high nitrogen steel.
article_number: '100023'
citation:
  ama: Kuball C-M, Jung R, Uhe B, Meschut G, Merklein M, eds. <i>Influence of the
    Process Temperature on the Forming Behaviour and the Friction during Bulk Forming
    of High Nitrogen Steel</i>. Vol 1.; 2020. doi:<a href="https://doi.org/10.1016/j.jajp.2020.100023">10.1016/j.jajp.2020.100023</a>
  apa: Kuball, C.-M., Jung, R., Uhe, B., Meschut, G., &#38; Merklein, M. (Eds.). (2020).
    <i>Influence of the process temperature on the forming behaviour and the friction
    during bulk forming of high nitrogen steel</i> (No. 100023; Vol. 1). <a href="https://doi.org/10.1016/j.jajp.2020.100023">https://doi.org/10.1016/j.jajp.2020.100023</a>
  bibtex: '@book{Kuball_Jung_Uhe_Meschut_Merklein_2020, series={Journal of Advanced
    Joining Processes}, title={Influence of the process temperature on the forming
    behaviour and the friction during bulk forming of high nitrogen steel}, volume={1},
    DOI={<a href="https://doi.org/10.1016/j.jajp.2020.100023">10.1016/j.jajp.2020.100023</a>},
    number={100023}, year={2020}, collection={Journal of Advanced Joining Processes}
    }'
  chicago: Kuball, Clara-Maria, R Jung, Benedikt Uhe, Gerson Meschut, and Marion Merklein,
    eds. <i>Influence of the Process Temperature on the Forming Behaviour and the
    Friction during Bulk Forming of High Nitrogen Steel</i>. Vol. 1. Journal of Advanced
    Joining Processes, 2020. <a href="https://doi.org/10.1016/j.jajp.2020.100023">https://doi.org/10.1016/j.jajp.2020.100023</a>.
  ieee: C.-M. Kuball, R. Jung, B. Uhe, G. Meschut, and M. Merklein, Eds., <i>Influence
    of the process temperature on the forming behaviour and the friction during bulk
    forming of high nitrogen steel</i>, vol. 1. 2020.
  mla: Kuball, Clara-Maria, et al., editors. <i>Influence of the Process Temperature
    on the Forming Behaviour and the Friction during Bulk Forming of High Nitrogen
    Steel</i>. 100023, 2020, doi:<a href="https://doi.org/10.1016/j.jajp.2020.100023">10.1016/j.jajp.2020.100023</a>.
  short: C.-M. Kuball, R. Jung, B. Uhe, G. Meschut, M. Merklein, eds., Influence of
    the Process Temperature on the Forming Behaviour and the Friction during Bulk
    Forming of High Nitrogen Steel, 2020.
date_created: 2020-10-12T08:23:27Z
date_updated: 2026-02-27T10:45:08Z
department:
- _id: '157'
doi: 10.1016/j.jajp.2020.100023
editor:
- first_name: Clara-Maria
  full_name: Kuball, Clara-Maria
  last_name: Kuball
- first_name: R
  full_name: Jung, R
  last_name: Jung
- 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: '         1'
keyword:
- High nitrogen steel
- Self-piercing riveting
- Joining by forming
- Bulk forming
- Strain hardening
language:
- iso: eng
publication_status: published
quality_controlled: '1'
series_title: Journal of Advanced Joining Processes
status: public
title: Influence of the process temperature on the forming behaviour and the friction
  during bulk forming of high nitrogen steel
type: conference_editor
user_id: '53912'
volume: 1
year: '2020'
...