电参数对 7075铝合金微弧氧化膜硬度的影响

通过使用直流双脉冲电源对 7075铝合金进行微弧氧化试验,研究了正向电压、占空比和脉冲频率等电参数对铝合金微弧氧化膜层硬度的影响。通过正交试验,研究了单一水平因素下的膜层硬度平均值的变化规律,发现了通过电参数提升膜层硬度的方法；通过相对极差分析,发现正向电压对膜层影响程度最大,脉冲频率对膜层影响程度最小。提出了针对 7075铝合金微弧氧化膜硬度提升的电参数优化方案:提升氧化膜硬度,应优先考虑增大正向电压；保证氧化膜硬度的同时兼顾其他表面性能,应优先调整对膜层硬度影响最小的脉冲频率。

Effect of Electrical Parameters on Hardness of Micro-Arc Oxidation Film of 7075 Aluminum Alloy

The micro-arc oxidation experiment of 7075 aluminum alloy is carried out by using the DC double pulse powersupply, the effects of electrical parameters such as positive voltage, duty cycle and pulse frequency on the hardness of themicro-arc oxidation film of 7075 aluminum alloy are studied. Through the orthogonal test, the variation law of the averagevalue of film hardness under a single level factor is studied, and the method of improving film hardness through electrical pa.rameters is found. Through the relative range analysis, it is found that the forward voltage has the greatest influence on thefilm and the pulse frequency has the least influence. The electrical parameter optimization scheme for improving the hard.ness of the arc oxidation film of 7075 aluminum alloy is proposed as follows: priority should be given to increasing the for.ward voltage in order to improve the hardness of oxide film; priority should be given to adjusting the pulse frequency, whichhas the least influence on the hardness of film, to ensure the hardness of oxide film and take into account other surface prop.erties.