The Effects of High-Energy Composite Surface Layer Modification on the Impact Performance of the H13 Steel Cutter Ring for Shield Tunneling Machine

The service life of the cutter ring of the shield tunneling machine affects the efficiency and cost of its tunneling. However, traditional heat treatment processes cannot simultaneously optimize both impact toughness and surface hardness, often leading to cracks or excessive wear of the cutter ring, greatly reducing their service life. According to the above situation, this paper applies high-energy composite modification treatment to H13 steel samples commonly used for the cutter ring of the hob and analyzes the impact toughness, hardness, microstructure, residual stress, and morphology characteristics of fracture of the samples under different high-energy composite modification processes. The study also investigates the effects of high-energy composite modification processes on the hardness and impact toughness of the samples. The experimental results show that the high-energy composite modification process enables the specimens to have good impact toughness and surface hardness simultaneously. The H13 steel sample has the best performance after carburizing, quenching, and laser shock modification, with a maximum surface hardness of 1017.5HV(0.2) and an impact toughness of 15.64 J/cm(2). Laser shock modification improves the surface residual compressive stress and hardness of H13 steel samples and also improves their impact toughness.