Plastic deformation behaviors and hardening mechanism of M7C3 carbide

Abstract This paper reports an investigation of inelastic deformation behaviors of M 7 C 3 carbide in high chromium cast iron by compression testing with a strain of 20% at 450 °C. The carbide exhibits plasticity and a work-hardening capacity upon compressive loading. Dislocations, twins and torsional deformation are introduced into the larger compressed block-shaped M 7 C 3 carbide. Multiple gliding and twist grain boundaries are firstly observed inside the deformed M 7 C 3 carbide. The corresponding microhardness of the compressed carbide measured at room temperature is found to increase by approximately 100 HV compared to the undeformed one. The plastic deformation behaviors of M 7 C 3 carbide provide a new and valuable understanding of the strain-hardening modes of carbide contained steel and iron materials.