二维超声复合电解/放电展成加工试验研究

Experimental Study of Two-Dimensional Ultrasound Combined Electrolysis/Discharge Generating Machining

为了提高铝基复合材料的表面成型质量和加工效率,提出了应用低电压、低电流密度的二维超声复合电解/放电展成加工(2UE/DM)技术。利用镀覆金刚石磨粒的工具侧面对复合材料进行3种不同工艺对比试验和3组参数下的性能试验,测量了铝基陶瓷增强复合材料(SiCp/Al)在质量分数0.5%的NaNO3溶液中展成加工时的电流、材料去除率(MRR)和表面粗糙度,探究了工具转速、电压和振幅对加工效率和质量的影响。结果表明,工件振动周期性改变加工间隙,单位周期内的放电频率增加了2倍;5000 r/min时放电频率减少,而表面粗糙度比1000 r/min降低了13.2%;在电压为6 V时,材料去除率达到0.89 mm^(3)/min,比3 V电压时增加45.9%,但较高电压导致裸露更多增强颗粒,比3 V时的表面粗糙度高出1.4μm;振幅增至5μm时,表面粗糙度比2μm时降低了17.5%,具有较高的加工质量。

To improve the surface forming quality and machining efficiency of aluminum matrix composites,a two-dimensional ultrasonic combined electrolysis/discharge generating machining technology(2UE/DM)with low voltage and low current density was proposed.Using the side of a tool coated with diamond grains,three different processing contrast tests and performance tests under three sets of parameters were carried out on the composite.The current,material removal rate(MRR)and surface roughness of SiCp/Al composites processed in 0.5%NaNO_(3)(mass fraction)solution were measured,and the effects of tool rotation speed,voltage and amplitude on processing efficiency and quality were explored.The results showed that the vibration of the workpiece periodically changed the machining gap,and the discharge frequency increased by 2 times per vibration period.At 5000 r/min,the discharge frequency decreased,the surface roughness decreased by 13.2% compared with 1000 r/min.At the voltage of 6 V,the material removal rate reached 0.89 mm^(3)/min,which was 45.9% higher than 3 V,but more reinforcing particles were exposed at the higher voltage,and the surface roughness was 1.4μm higher than 3 V.When the amplitude increases to 5μm,the surface roughness was 17.5% lower than 2μm,and the technology had higher machining quality.