Effect of heat treatment process on microstructure and residual stress distribution in HSS punch

Le résumé fourni par la source

To optimize the heat treatment process and enhance the performance of M42 high-speed steel punches, which are prone to edge collapse failure during service due to residual stress, this study systematically investigated the regulatory effect of spheroidizing annealing pre-treatment on the microstructure and residual stress distribution in M42 high-speed steel punches throughout the complete quenching and tempering process chain. Two heat treatment routes, with and without spheroidizing annealing, were designed. Scanning electron microscopy(SEM) and X-ray diffractometry(XRD) were employed to characterize the microstructure and surface residual stress of the punches at different process stages, and ABAQUS finite element software was used to simulate the residual stress evolution during the entire process. The results show that spheroidizing annealing can release 70%~90% of the initial residual stress introduced by extrusion processing and significantly improve the stress distribution after final heat treatment. Notably, at the critical root area where the punch is prone to failure, the stress state is optimized from a compressive stress of -400 MPa to a tensile stress of +100 MPa, which is beneficial for counteracting the service loads. Concurrently, spheroidizing annealing significantly enhances the proportion of fine carbides smaller than 1.5 μm in the microstructure, exhibiting a uniform and dispersed distribution. Adding spheroidizing annealing pre-treatment is an effective means to optimize the residual stress distribution and refine carbides in M42 high-speed steel punches. This study reveals its underlying mechanisms and provides reference for the heat treatment process design of high-performance punches.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.