Investigation of the Influence of Static Recrystallization on Void Evolution After Hot Compression Forming

Damage that exists in the form of microvoids in a material can be influenced by various process parameters during forming. Depending on these parameters, the static recrystallization (SRX) occurring during the holding time between two hot forming steps can also lead to a reduction in damage. Therefore, this work aims to investigate the influence of SRX on ductile damage after hot compression forming in the case hardening steel 16MnCrS5. First, stress relaxation tests are conducted to characterize the kinetics of static recrystallization in the material. Based on that, hot compression tests are performed at different temperatures and holding times. The void area fraction (VAF) after the hot compression and consecutive static recrystallization is determined based on combined image processing of scanning-electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX). The results show a decrease in VAF with an increasing recrystallized volume fraction, which indicates a positive effect of static recrystallization on void healing.