2A06铝合金表面微弧氧化陶瓷层摩擦学特性  

Tribological Performance of Ceramic Composite Coatings Obtained by Microarc Oxidation on 2A06 Aluminum Alloy

作　　者：李淑华[1,2] 沈大为[3] 祖媛媛[4] 曲长征[1] 王富耻[2] 冯顺山[2] 

机构地区：[1]中国人民解放军军械工程学院 [2]北京理工大学 [3]中国人民解放军62025部队 [4]中国人民解放军军需装备研究所

出　　处：《稀有金属材料与工程》2014年第1期154-157,共4页Rare Metal Materials and Engineering

摘　　要：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。A dense ceramic oxide coating with approximate 40 Ixm thickness was prepared on 2A06 aluminum alloy by means of microarc oxidation in an alkali-silicate electrolytic solution. The morphology and the microstructure were analyzed by scanning electron microscope （SEM） and X-ray diffraction （XRD）. Coating thickness and surface roughness （Ra） were measured after the coating was synthesized. The tribological performance of the coatings was evaluated using a dry sand abrasion test and a solid particle erosion test. The results show that microarc oxidation coatings consist of the loose superficial layer and the inner dense layer. Both the inner layer and the outer layer are composed of a-A1203 and y-A1203, While the A16Si203 phase is observed only in the outer loose layer, and the inner layer has a higher content of a-A1203 than that of the outer layer. The average of the microhardness of the ceramic coatings is 20.96 GPa. Moreover, under the same experimental condition, the specific wear rate of ceramic coating is smaller than that of 2A06 aluminum alloy which indicates the friction and the wear properties of the 2A06 aluminum alloy are improved and the lifetime of 2A06 aluminum alloy employed in harsh environments is extended with the increase of coating thickness and quality improvement.

关 键 词：2A06铝合金 微弧氧化 陶瓷层 摩擦学特性 

分 类 号：TG174.45[金属学及工艺—金属表面处理] TG146.21[金属学及工艺—金属学]