Electrical discharge machining of Ti6Al4V alloy with nitrogen gas assistance

Due to its exceptional performance, the Ti6Al4V alloy finds extensive use in aviation, biomedical, and petrochemical sectors. Nonetheless, its limited machinability and subpar wear resistance have hindered its widespread application. Therefore, this study underlooks a novel approach by employing nitrogen (N2) gas-assisted electrical discharge machining (NA-EDM) to machine Ti6Al4V. In this context, N-2 gas serves a dual purpose. On the one hand, the flow of N-2 has a beneficial impact on enhancing the surface properties of the workpiece. On the other hand, N2 reacts with titanium (Ti) to create titanium nitride (TiN), enhancing the component's performance. Also, this study focuses on investigating how peak current, pulse-on time, electrode rotation speed, and gas pressure influence various aspects, including surface morphology, surface roughness, the microstructure of the recast layer, the microhardness of the recast layer, the thickness of the recast layer, and material removal rate (MRR). Experimental findings show that the NA-EDM process results in a smoother surface morphology, a uniform recast layer, and a reduced MRR. The microhardness in NA-EDM exceeds that of EDM by 42.1%, attributed to the formation of TiN and martensite. Ra is decreased by 21.2% compared to EDM. This study offers novel insights into machining Ti6Al4V alloy, opening up possibilities for broader-scale applications.