The effect and mechanism of ultrasonic vibration on the microstructure and performance of laser cladding 316L coating has been studied, providing a theoretical basis and technical support for the application of the ultrasonic-assisted laser cladding process. The results show that ultrasonic vibrations with different amplitudes can effectively improve the macroscopic forming quality of the cladding layer, among which the ultrasonic vibration with 17.5 μm amplitude is the best. Ultrasonic vibration can also significantly improve the micro-forming quality of the cladding layer, such as homogenizing the structure, refining grains and reducing porosity. The wear mechanism of the cladding layer with an ultrasonic assistance of 17.5 μm is mainly abrasive wear, so the wear resistance has been significantly improved. The ultrasonic-assisted cladding layer exhibits significant passivation behavior in 3.5 wt% NaCl solution. It may be that the surface roughness reduction and grain refinement caused by ultrasonic assistance can improve the integrity and compactness of the cladding layer, so the dynamic equilibrium process of the dissolution and reformation of the passive film is changed, which can improve the corrosion resistance of the surface. There are some equiaxed grains in the columnar-grains area of the ultrasonic-assisted cladding layer, mainly because the inside of some primary columnar grains has gone through a process of lattice distortion → dislocation multiplication → substructure rotation → formation of small-angle grain boundary → misorientation accumulation → formation of new grains in the process of ultrasonic-assisted laser cladding of 316L stainless steel.

研究了超声振动对激光熔覆316L涂层显微组织和性能的影响及机理，为超声辅助激光熔覆工艺的应用提供了理论依据和技术支持。结果表明，不同振幅的超声振动能有效提高熔覆层的宏观成形质量，其中以17.5 μm振幅的超声振动效果最好。超声波振动还可以显着提高熔覆层的微成形质量，如使组织均匀化、细化晶粒和降低孔隙率。17.5 μm超声辅助熔覆层的磨损机理主要是磨粒磨损，因此耐磨性得到了显着提高。超声辅助熔覆层在 3.5 wt% NaCl 溶液中表现出显着的钝化行为。可能是超声辅助引起的表面粗糙度降低和晶粒细化可以提高熔覆层的完整性和致密性，从而改变钝化膜溶解和重整的动态平衡过程，从而可以提高熔覆层的耐蚀性。表面。超声辅助熔覆层的柱状晶粒区域有一些等轴晶粒，