黄铜电极对直流短电弧铣削Ti-6Al-4V的加工实验探究

Research on the machining experiment of Ti-6Al-4V by DC short arc milling with brass electrode

短电弧铣削加工技术是一种针对难加工导电材料具有高效去除率的放电加工方法,但是由于脉冲电源输出功率的限制难以达到高效的目的。采用黄铜作为阴极刀具材料,对Ti-6Al-4V进行直流短电弧铣削加工实验,研究不同工艺参数(电压幅值、主轴转速及工作介质压力)下对加工过程中材料去除率(MRR)、相对电极损耗(TWR)、能耗(SEC)和表面粗糙度(Sa)的影响规律;并结合数据采集系统和高速摄像仪对加工过程中的电压电流数据和电弧形态进行分析,通过工件的微观形貌、能谱分析和硬度测试探索直流短电弧铣削的加工机理。实验表明:随着电压升高,MRR和Sa增加,MRR在电压为30 V时达到2906 mm^(3)/min,TWR和SEC随电压升高而降低;随工作介质压力增加,SEC增加,TWR和Sa降低,MRR在0.3 MPa时达到最大值;在主轴转速增加时,MRR、SEC和Sa增加,TWR呈降低趋势。

Short electric arc milling technology is a kind of electrical discharge machining method with high removal rate for difficult to machine conductive materials,but it is difficult to achieve high efficiency due to the limitation of output power of pulse power supply.In this paper,using brass as cathode tool material,the DC short electric arc electric milling experiment of Ti-6 Al-4 V was carried out to study the influence of different process parameters(voltage amplitude,spindle speed,working medium pressure)on the material removal rate(MRR),relative electrode loss(TWR),energy consumption(SEC)and surface roughness(Sa)in the processing process The voltage and current data and arc shape in the process of machining are analyzed by speed camera.The machining mechanism of DC short electric arc milling is explored through the micro morphology,energy spectrum analysis and hardness test of the workpiece.The experimental results show that:with the increase of voltage,MRR and Sa increase,MRR reaches 2906 mm/min at 30 V,TWR and SEC decrease with the increase of voltage;with the increase of working medium pressure,SEC increases,TWR and Sa decrease,MRR reaches the maximum at 0.3 MPa;with the increase of spindle speed,MRR,SEC and Sa increase,TWR decreases.