Enhancing machinability of Ti6Al4V by ultrashort-pulse laser-induced modification assisted grinding

As an essential structural metal in the aerospace industry, titanium alloys are widely used in the manufacture of aero-engine blades and compressor key parts. However, it is difficult to achieve efficient machining by using conventional methods due to its high hardness, high strength, and low thermal conductivity. A novel ultrashort-pulse laser-induced modification assisted grinding (LIMAG) method is proposed in this study to enhance the machinability of materials by laser-induced modification of their surface layers. The laser-induced modification mechanism of Ti6Al4V was investigated in terms of the microscopic morphological structure, elemental distribution, and chemical states of the modified layer; the grinding performance of LIMAG was evaluated by comparison with conventional grinding (COG); and the material removal mechanism of LIMAG was investigated. It was found that the chemically modified layer consisted of a fluffy compound layer consisting of various types of microscopic copolymer mixture particles and a transition layer, and that the reaction products of laser-induced Ti6Al4V were TiN, TiO2, and Al2O3. The grinding force, surface roughness, and grit wear of LIMAG were significantly reduced. Consequently, surface integrity and abrasive belt life are significantly improved. The work provides a vital high-performance processing method for titanium alloy components.