纯钨材料环形微槽电解电火花加工特性研究

Study on Electrochemical Discharge Machining of Micro-Groove on Pure Tungsten

为解决氙灯钨阳极表面密集环形微槽加工的技术问题,提出了采用RC电源,在超低电导率下电解电火花加工纯钨表面微沟槽的方法。研究在RC电源下,不同电解液类型下的电解电火花加工特性。首先,通过电化学工作站测量纯钨材料在不同电解液类型下的极化曲线,分析不同电解液类型的初腐蚀电位。为研究加工过程形成的气泡对加工的影响规律,通过高速摄像仪对不同工艺条件下加工区域的气泡形成与分布进行观察。最后,采用自主研制的试验装置开展了纯钨棒材表面环形微沟槽电解电火花加工工艺试验,分析工作液成分、电导率、转速和电压不同参数对加工特性的影响规律。在极间电压60V,转速500r/min,电导率为50μS/cm的NaOH电解液下加工了槽宽为50.97μm,槽深为17.31μm的微沟槽结构。

In order to solve the technical problem of dense micro grooves on the surface of xenon lamp tungsten anode, a method of electrochemical discharge machining(ECDM) of micro grooves on pure tungsten at low conductivity electrolyte was proposed, and RC power supply was applied into the process. The characteristics of ECDM with different electrolyte under RC power supply were studied. Firstly, the polarization curves of pure tungsten materials under different electrolytes were measured by electrochemical workstation, and the open circuit potential at different electrolytes was analyzed. In order to study the influence of the bubbles distribution during the processing, the bubbles formation and distribution in the machining area under different experimental conditions were observed by high-speed camera. Finally, the process of ECDM of micro-groove on the surface of pure tungsten rod was carried out with self-developed test device. The effects of electrolyte type, conductivity, rotational speed and inter electrode voltage on the machining characteristics were analyzed. Under 50μS/cm NaOH solution with an inter electrode voltage of 60 V and a rotating speed of 500 r/min, the micro groove with width is 50.97μm and the depth is 17.31μm was obtained by ECDM.