Overview of residual stress after quenching. Part II: factors affecting quench residual stresses

Abstract

The paper deals with both the internal stresses occurring during steel quenching in various heat-treatment processes for steels and the occurrence of residual stresses. Residual stresses are caused by plastification of a material on a micro-level, which results in the distortion of machine parts and residual stresses. The paper treats residual stresses in induction surface hardening and case-hardening of the machine parts and gears subjected to dynamic loads during their operation. Special attention is paid to the influences of surface heat treatment, final grinding to size, and residual-stress profiles. Results obtained by numerous researchers investigating influences of different quenching conditions, taking into account different quenching media and different temperatures of quenching media, standing still or in motion, are presented. A comparison of the relevant fatigue strengths obtained after various thermo-chemical processes of hardening combined with polishing or honing, and strain hardening is given. The paper gives a review of investigations conducted in the field of quenching and distortion in terms of quenching agents, quenching issues, and results of quenching such as hardness, residual stresses, volume changes, and distortion.