Experimental investigation on Ti2AlNb in high-efficiency short electric arc milling

Ti2AlNb is a typical hard cutting material whose high strength and hardness result in a low traditional mechanical cutting efficiency and high tool wear. Short electric arc milling (SEAM) is a non-contact machining method whose machining process is unaffected by the material itself. It shows good machining performance and a high machining efficiency for Ti2AlNb materials. In this paper, the effects of the milling method, electrode material, and W-Cu alloy electrode on the sidewall properties of Ti2AlNb materials milled by SEAM were investigated. We used material removal rate (MRR), relative electrode wear ratio (REWR), and surface roughness (Ra) as technical indicators. The experiments showed that the W-Cu alloy electrode was more suitable for the rough machining of Ti2AlNb materials. Up-milled Ti2AlNb showed a high surface quality. Compared with a copper–graphite electrode, the MRR and REWR of W-Cu alloy is twice and 1/8 that of copper–graphite. The maximum thickness of the recast layer and heat-affected layer on the workpiece surface after W-Cu alloy electrodes is about 3.3 times and 3.1 times that of copper–graphite. This work provides a theoretical basis and practical reference for the efficient, high-quality, and high-precision short arc machining of Ti2AlNb materials.