Graduate School

Project B2: Analysis of changes in residual stresses and distortions resulting from case hardening in hard processing

Person in Charge: Dipl. Ing. Tobias Strauß
  Motivation and aim:
The main objective of the project is to determine the local residual stress distributions of an automotive gearshift sleeve after the process steps soft-machining, case/induction hardening and hard machining. In order to achieve this aim a strategy to measure local residual stress distributions at the tooth-root-surface of the inner gearing has to be develop. This strategy will be based on residual stress measurement methods which are available at any time like conventional laboratory X-ray sources. The gearshift sleeve reflects a typical industrial solid component with a complex geometry.  
Investigations Results

Residual stress measurements using laboratory X-ray sources and mechanical methods.
For the validation of the process simulations and in order to develop a strategy residual stress analyses were carried out by means of energy dispersive diffraction using high energy synchrotron X-ray radiation (EDXRD) and neutron diffraction.

  • Experimental measurement and evaluation strategy to measure local residual stress distribution at the gearshift sleeve
  • Residual stress redistribution at the tooth root surface of the inner gearing
  • Studies to identify the effects of broaching parameters on the  surface layer conditions and residual stress state
  • MAXIM-method (MAterials X-ray IMaging) for studies with high lateral/spatial resolution
  • Data base for the simulation validation