Enhancing coating performance: Design and characterization of a Ti-Al-Si-Cr-SiC system coating using ultrasonic and rare earth assisted laser cladding

This study proposes the utilization of rare earth combined with ultrasonic-assisted laser cladding technology to address the dilution problem encountered during the laser cladding coating of Ti alloy. The aim is to improve the performance of the coating. Using Ti alloy surface as a base, a novel Ti-Al-Si-Cr-SiC multi-principal element alloy coating is fabricated. To characterize the coating, various techniques such as transmission electron microscopy (TEM), electron backscatter diffraction (EBSD), and scanning electron microscopy (SEM) are employed to examine the microstructure and phase composition. The interface between the coating and the substrate is analyzed using focused ion beam and TEM. The coatings are also evaluated for corrosion and wear resistance through potentiodynamic polarization, electrochemical impedance spectroscopy, hardness, and friction tests. The results reveal that the rare earth combined with ultrasonic-assisted Ti-Al-Si-Cr-SiC coating consists of Ti4Cr phase, TiC phase, and eutectic phase (Ti3Al and Ti5Si3). The combined effect of ultrasonic energy and rare earth reduces the dilution rate of the coating, resulting in a refined coating structure that improves the wear resistance and corrosion resistance.