Effect of Ultrasonic Vibration on Microstructure and Properties of Ni‐Based Cladding Layers Reinforced by Chromium Carbide In Situ Generated

Multi‐layer coatings were prepared using ultrasonic frequencies to enhance coating performance. First, experiments were conducted on multilayer coatings with different overlap ratios. A comprehensive analysis of the macro‐ and microstructures determined the optimal overlap ratio. Then, ultrasonic‐assisted experiments were performed to analyze the shape of the melt pool during ultrasonic‐assisted cladding. Finally, microhardness testing and friction wear experiments were conducted on the cladding layer surfaces before and after ultrasonic assistance. The results revealed that the ultrasonic field resulted in a more uniform distribution of hardness and wear resistance in the cladding layers. The results indicate that the macro‐level performance of the coating is optimal when the overlap ratio is 40%. Before ultrasonic application, the coating structure consists primarily of randomly oriented coarse dendrites. After ultrasonic application, the phase composition of the coating remained unchanged; however, the dendrites were more densely arranged, and their sizes decreased. The coating's microhardness increased from 591.07 HV 0.5 to 624.98 HV 0.5 with ultrasonic influence. Additionally, the wear volume and wear rate increased by 30% and 40%, respectively. The wear mechanism changed from plowing, accumulation, and adhesive wear to mild plowing.