Improved process understanding of case hardening with low pressure carburizing based on in-situ X-ray diffraction experiments

Motivation

Low pressure case-hardening is an environmentally friendly and economical process, which is used to realize a hart and wear resistant surface with a sufficiently ductile core. By the compressive residual stresses induced through quenching and the associated martensitic hardening the fatigue behaviour is improved. Case-hardening is a state of the art fabrication process for surface hardening of highly stressed components, such as gear wheels and shafts, which are used for example in power plants or in automotive drive trains.

Objective

  • Fundamental process understanding for low pressure case hardening
  • Evaluation of transformation kinetics and of the microstructure evolution
  • Knowledge of temporal and spatial development of phase specific stresses

Analyses

  • In-situ process analysis by synchrotron X-ray analyses with angular and energy dispersive experimental setups
  • In-situ process analysis using laboratory setups
  • Ex-situ characterisation with conventionally generated X-rays and metallographic examinations /micro hardness measurement

This project is DFG founded and realized in cooperation with the group “Physical Analysis” at Leibniz Institute for Materials Engineering (IWT) in Bremen.