Research progress on laser additive remanufacturing of critical load-bearing components for railway vehicles

Railway transportation is the main artery of the national economy, developing towards high speed, heavy load, and complex application environments. The performance and service safety of critical load-bearing components of railway vehicles (such as rotating parts including wheels, axles, and brake discs) are crucial, and they have long faced common problems such as wear and fatigue damage failure. Conventional repair methods usually have problems such as large heat input, large deformation, and easy failure in the bonding zone. Laser additive remanufacturing technology has advantages such as high bonding strength, controllable dilution rate and heat-affected zone, and small thermal deformation, which provides a new solution for the high-quality repair and remanufacturing of metal components and has received widespread attention. In this paper, the damage and failure modes of critical load-bearing components of railway vehicles were primarily summarized. The laser additive remanufacturing technology and its classification were outlined from the perspective of technical principles and characteristics. Centering on material development, process monitoring, process optimization, and fundamental performance evaluation, the Chinese and international research status of additive remanufacturing for critical components of railway vehicles was summarized. Furthermore, the current technical challenges were pointed out, and future development opportunities were prospected to promote the sustainable development of the rail transit remanufacturing industry.