20CrMnTi surface strengthening based on laser-assisted carburizing grinding

Abstract

Highly wear-resistant 20CrMnTi surfaces with gradient properties are urgently demanded in manufacturing core components such as shafts and gears. However, balancing productivity, production costs, and energy consumption with existing surface machining and strengthening methods are challenging. Therefore, laser-assisted carburizing grinding is proposed, which combines laser micro-carburizing and grinding tempering to realize the integration of processing and strengthening of the 20CrMnTi surface. The optimal laser power is determined to be 300 W by the dynamic thermal-force coupling effect. A 1300 μm thick metamorphic layer is formed on the surface of 20CrMnTi, and its formation mechanism is analyzed based on the microstructural phase transformation. The surface hardness after laser-assisted carburizing grinding can reach 550 HV. The failure form of the carburized surface is mainly abrasive wear, and the wear loss is reduced to 50% compared to uncarburized surfaces. This study developed an efficient, energy-saving, and controllable integrated method of 20CrMnTi surface machining and strengthening. Meanwhile, the surface strengthening mechanism is explained based on laser micro-carburizing and grinding tempering. The findings provide technical references for manufacturing high-performance 20CrMnTi surfaces and theoretical support for carburized grinding strengthening technology.