A Review of High Wear-Resistant Fe-Based Laser Clad Coatings: Alloy Design, Process Optimization and Post-Treatment

High-wear-resistant iron-based clad layers demonstrate substantial application potential in aerospace, automotive, and industrial equipment due to their excellent mechanical properties and extended service life. Laser cladding has emerged as a pivotal technology for the additive manufacturing and repair of critical components, characterized by rapid cooling rates, narrow heat-affected zones, and dense microstructures. However, fabricating high-wear-resistant Fe-based clad layers remains challenging, particularly in achieving a trade-off among hardness, wear resistance, and toughness. Excessively high hardness often compromises toughness, increasing susceptibility to cracking and reducing service reliability, whereas insufficient hardness undermines functional performance and shortens service life. This review synthesizes recent advances in microstructural design, control, and optimization of high-wear-resistant Fe-based clad layers, focusing on powder alloying design, process parameter optimization, and post-cladding strengthening treatments. The strengthening mechanisms and performance characteristics of key alloying elements, specifically Cr, B, Nb, Mo, and Ti, are summarized, and the effects of laser power, scanning speed, and powder feeding rate on the microstructure and properties are systematically discussed. Furthermore, the influence of post-treatment processes, including turning, grinding, ultrasonic rolling, and heat treatment, on wear resistance enhancement is also addressed. Finally, future development directions for laser cladding of high-wear-resistant Fe-based clad layers are proposed.