Investigation of the structure characteristics and formation mechanisms of pure molybdenum metal alloy induced by laser processing and laser water-assisted processing

Due to the characteristics of low-temperature brittle conversion of metal molybdenum, it will affect its performance under high-temperature conditions. This paper first established a computational model for the solid/liquid/gas three-phase system to analyze material removal characteristics, temperature fields, and recast layer dimensions of Molybdenum metal induced by laser processing and laser water-assisted processing. Then a processing experimental platform was constructed, and the microstructure, organization, and elemental content of the laser-processed edges were tested using SEM, micro-XRD, and EDS techniques. The results indicate that the novel water-assisted laser processing method can accelerate the cooling rate of the laser-affected surface and suppress the formation of recast layers at the cutting boundary. Additionally, water can isolate the interaction between oxygen in the air and molybdenum, effectively reducing the generation of molybdenum dioxide. However, when water is excited by the laser, it can produce a large number of ionized electrons, leading to the deposition of particulate products on the metal surface. The findings of this study provide a theoretical basis for efficient and high-quality processing of difficult-to-machine metal materials. Laser water-assisted processing can be used as a new processing method for hard and brittle materials.