Effects of Laser Oscillation Frequency on the Microstructure and Properties of TiC/Fe‐Based Alloy Composite Coatings

Abstract

Herein, TiC/Fe‐based alloys are melted and deposited on a 45‐steel substrate by using an oscillating laser with an 8‐shaped trajectory. Four samples are prepared to investigate the phase changes and microstructure characteristics using laser cladding under different oscillation frequencies. The microhardness, wear resistance, and electrochemical corrosion performance on both substrate and coatings are thoroughly evaluated. The results show that with TiC particles uniformly distributed throughout the coatings, the cladded coatings primarily composed of α‐Fe, (Cr, Fe)7C3, M2B (Cr, Fe), and TiC phases contribute to refined grains and enhanced mechanical strength; additionally, an increase in oscillation frequency leads to further grain refinement, which significantly improves the microhardness of coatings; however, higher hardness does not guarantee better wear resistance; the presence of cracks can actually decrease the coating's durability against wear. It is found that the coating with an oscillation frequency of 200 Hz not only achieves the best wear resistance, but also exhibits excellent electrochemical performance.