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采用微弧氧化技术,以硅酸盐为主要电解液,在2A06铝合金表面制备出高硬度、高耐磨性的微弧氧化陶瓷膜。用扫描电镜观测膜层的显微结构,用X射线衍射分析其相组成,并对膜层进行耐磨损和抗冲蚀试验。结果表明,氧化时间越长,2A06铝合金表面陶瓷层越厚,陶瓷层粗糙度也越高。陶瓷层由过渡层、致密层和疏松层组成。过渡层与基体和致密层结合紧密。致密层的相组成主要为α-Al2O3、γ-Al2O3,疏松层的相组成主要为α-Al2O3、γ-Al2O3以及Al6Si2O3。致密层中的α-Al2O3相的含量远高于疏松层。从试样边缘到试样中心硬度逐渐降低,最高硬度出现在试样表面边缘向内5～20 mm处,平均HV硬度可达20.96 GPa。2A06铝合金的耐磨性比较差,磨轮转速从100 r/min增至400 r/min时,磨损量不断增加且呈线性分布。微弧氧化制备的陶瓷层磨损量在磨损开始时(100 r/min)稍高,磨轮转速到600 r/min时磨损量趋于稳定,磨轮转速到1600 r/min时磨损量仍然呈现较低水平。陶瓷层的冲蚀体积损失率也远低于2A06铝合金基体。
The micro-arc oxidation ceramic membrane with high hardness and high wear resistance was prepared on 2A06 aluminum alloy by using micro-arc oxidation technology and silicate as the main electrolyte. The microstructure of the film was observed by SEM, the phase composition was analyzed by X-ray diffraction, and the wear resistance and erosion resistance of the film were tested. The results show that the longer the oxidation time, the thicker the ceramic layer on the 2A06 aluminum alloy and the higher the roughness of the ceramic layer. Ceramic layer by the transitional layer, dense layer and loose layer. Transitional layer and the matrix and dense layer closely. The phase composition of the dense layer is mainly α-Al2O3, γ-Al2O3. The phase composition of the bulk layer is mainly α-Al2O3, γ-Al2O3 and Al6Si2O3. The content of α-Al2O3 phase in the dense layer is much higher than that of the loose layer. The hardness gradually decreases from the edge of the specimen to the center of the specimen, and the highest hardness appears 5 to 20 mm inward from the edge of the specimen surface, with an average HV hardness of 20.96 GPa. 2A06 aluminum alloy wear resistance is relatively poor, grinding wheel speed increased from 100 r / min to 400 r / min, the wear increased and linear distribution. The wear amount of the ceramic layer prepared by micro-arc oxidation is slightly higher at the beginning of wear (100 r / min), and the wear amount tends to be stable when the rotation speed of the grinding wheel reaches 600 r / min. Level. Ceramic layer erosion volume loss rate is also much lower than 2A06 aluminum alloy substrate.