钛合金电火花多次切割表面气体强化研究

Research on Gas Intensifying Titanium Alloy's Surface in Multi-cutting of WEDM

分析了采用电火花线切割多次切割工艺对钛合金进行表面气体强化处理的可行性,前几次切割采用复合工作液为冷却介质,最后一次采用压缩空气或氮气作为放电介质,对钛合金加工表面进行强化。对比实验表明,以气体作为强化介质时,加工表面硬度得到明显提高,采用氮气进行强化的表面显微硬度达到2050 HV,是基体的486%,形成了氮化钛组分,且表面基本不存在电解微孔洞和显微裂纹,表面完整性也得到明显改善。

This paper analyzes the feasibility of multi-cutting of WEDM in the surface strengthening of Titanium alloy with gas. In the previous times of multi-cutting, the composite liquid is used as cooling medium, while high-pressure air or nitrogen is chosen in the last cutting during surface strengthening of Titanium alloy processed by EDM. Comparative experiment indicates that the hardhess of machined surface is improved obviously when the gas is chosen as the intensified medium in the last cutting, meanwhile, the micro-hardness of the intensified surface reaches HV 2050, 486 % higher than the substrate, with nitrogen chosen as the intensified medium in the last cutting. The result proves that Titanium Nitride component has already generated in the surface with no electrolytic micro-void and micro-creak, the surface integrity is also improved significantly.