Paper Title:
A Physically Based Model for Bake-Hardening Steels and Dent Resistance
  Abstract

Arcelor produces « Bake-Hardening » steels for automotive outer panels, which present the advantages of a remarkable drawability combined with a significant hardening after stamping and paint baking by the car maker. This hardening enables to increase the dent resistance of those automotive parts. In order to give easy design criterion and support the development for new “bake-hardening” steels, a physically-based model for Bake-Hardening steels has been developed. It is suitable to predict: -the physical phenomenon of strain ageing based on Cottrell atmospheres formation. A detailed description of the strain ageing kinetics is given based on a generalized form of the Harper model taking into account the diffusion of carbon atoms in the stress field of a dislocation, progressive carbon depletion in the matrix and saturation of the available dislocation sites. -the plastic instabilities propagation during tensile testing according to Piobert–Lüders phenomenon using the finite element method. A local mechanical behaviour is introduced whose shape schematically describes the local dislocation behaviour. The effect of the grain size on the velocity of the Lüders’ band front is especially enlightened. -the effect of ageing process on dent resistance. To do so, a physical extension of the former approach to more complex loading paths is proposed.

  Info
Periodical
Materials Science Forum (Volumes 539-543)
Main Theme
Edited by
T. Chandra, K. Tsuzaki, M. Militzer , C. Ravindran
Pages
4232-4237
DOI
10.4028/www.scientific.net/MSF.539-543.4232
Citation
J. L. Uriarte, A. Perlade, X. Lemoine, M. Soler, V. Ballarin, T. Iung, "A Physically Based Model for Bake-Hardening Steels and Dent Resistance", Materials Science Forum, Vols. 539-543, pp. 4232-4237, 2007
Online since
March 2007
Export
Price
$32.00
Share

In order to see related information, you need to Login.

In order to see related information, you need to Login.

Authors: Elena V. Pereloma, V. Bata, R.I. Scott, R.M. Smith
Abstract:This work explores the effect of Cr addition on the kinetics of strain ageing process. The strain ageing behaviour of low carbon steel with...
4214
Authors: B.I. Rodgers, R.J. Cinderey, Philip B. Prangnell
Chapter 2: Phase Transformations
Abstract:The influence of larger pre-strains, than are currently used in industry, has been investigated on the ageing behaviour of the Al-Cu-Li alloy...
205
Authors: Johannes Kreyca, Ahmad Falahati, Ernst Kozeschnik
Chapter 2: Contributed Papers
Abstract:The yield strength of an A6061 Aluminium alloy for different artificial ageing times, strain rates and temperatures is modelled taking into...
1014