负脉冲对铝合金微弧氧化的影响

Influence of negative pulse on aluminum alloy micro-arc oxidation

采用自行研制的100 kW大功率微弧氧化电源设备,对LY12铝合金进行表面处理。研究了加载不同个数负脉冲时,铝合金微弧氧化处理过程中电压、电流的变化规律,并利用涡流测厚仪和表面粗糙度仪对陶瓷层的生长厚度及表面粗糙度进行测量。试验结果表明:随着负脉冲个数的增加,负电流值也随之增加;负脉冲个数越多,陶瓷层的生长时间越短,相反溶解时间越长;在相同处理时间内,陶瓷层的生长厚度和表面粗糙度均随负脉冲个数的增加而降低。该现象与负脉冲加载过程中陶瓷层的溶解反应相关。

LY12 alloy was processed with 100 kW micro-arc oxidation（MAO） power. The study works include the changing relationship of voltage and current, the thickness and surface roughness of the aluminum alloy MAO ceramic layer measured with special instrument. The results show that negative current increases with the negative pulses increasing~ the growth periods of ceramic layer decreases as negative pulses increasing, while the dissolution periods increaes; the thickness and surface roughness of the ceramic layer decrease as the number of negative pulses increasing, within the same processing time. It is found that this relates to the dissolution reaction of ceramic layer during the negative pulses loading period. 1 tab, 6 figs, 10 refs.