Characterization of the plasticity parameters of the surface-modified layer of 18CrNiMo7-6 alloy steel after carburizing heat treatment through the indentation method

Abstract

A surface-modified layer (SML) can play an important role in the durability and in-service behavior of key components, but characterization of the mechanical properties of SML is complex. In this paper, an indentation method to characterize the plastic parameters of the SML is proposed. The method combines indentation tests and finite element simulation to analyze the plastic parameters of the SML. The yield strength and hardening index of the SML for 18CrNiMo7-6 alloy steel, before and after heat treatment, were characterized using the proposed method. After heat treatment, the yield strength and hardening index decreased gradually along the depth. The results obtained agree with the tensile test results.

Keywords

• Indentation test
• Surface-modified layers
• Plasticity parameters
• Yield strength
• Hardening index