Minimizing Case/Core Initiated Failures in Induction Hardened Components

摘要

Induction case hardening experiments were performed by heat treat simulation for a large section cylinder of SAE 4140 steel. The simulation is first calibrated to experimental induction hardening results on SAE 4140 steel. Results are presented showing hardness vs. depth and residual stress vs. depth results on prior heat treat and induction processing parameter combinations. The hardness and residual stress levels at the case/core interface and transition region are examined. The goal is to identify material and processing combinations that will prevent case to core transition initiated failures in pins or shafts with high bending or torsional loads. Results are discussed with this in mind. The use of heat treat simulation aids in this thought process and saves laboratory test time and money.