优化7075铝合金阳极氧化膜性能的工艺探究

Exploration of Optimization Process for Anodic Oxidation Film Performance of 7075 Aluminum Alloy

采用硫酸直流阳极氧化法对7075铝合金表面进行硬质阳极氧化。利用正交试验研究了氧化温度、氧化时间、电流密度、硫酸浓度及草酸浓度对氧化膜厚度与硬度的影响。运用极差分析法对不同工艺制得的氧化膜硬度与厚度进行分析。结果表明:在氧化温度5℃,电流密度4 A/dm^2,硫酸浓度100 g/L,草酸浓度10 g/L,氧化时间90 min制得的氧化膜最厚,为104.5μm。在氧化温度5℃,电流密度3 A/dm^2,硫酸浓度100 g/L,草酸浓度25 g/L,氧化时间30 min时制得的氧化膜表面硬度最高,为408 HV0.05。

The hard anodic oxidation on the surface of 7075 aluminum alloy was carried out by sulfuric acid direct current anodic oxidation method. The effects of oxidation temperature, oxidation time, current density, concentration of sulfuric acid and oxalic acid on the hardness and thickness of the oxide films were studied by orthogonal experiment research methods. The hardness and thickness of the oxide films prepared by different processes were analyzed by range analysis method. The results show that under the oxidation temperature of 5℃, the current density of 4 A/dm^2, sulfuric acid concentration of 100 g/L, oxalic acid concentration of 10 g/L, oxidation time of 90 min, the thickness of the obtained oxide film is thickest, which is 104.5 μm. Under the oxidation temperature of 5 ℃, the current density of 3 A/dm^2, the sulfuric acid concentration of 100 g/L, the oxalic acid concentration of 25 g/L, the oxidation time of 30 min, the oxide film with highest hardness can be obtained, which is 408 HV0.05.