镁合金表面微弧氧化陶瓷层摩擦学性能的研究

Study on the Tribological Behavior of Micro-arc Oxidized Ceramic Coatings on Magnesium Alloy Surfaces

利用微弧氧化技术在AZ31镁合金表面原位生长陶瓷层,用球-盘磨损实验机对试样的摩擦学性能进行了研究。结果表明:AZ31镁合金表面微弧氧化后可以形成均匀的表面陶瓷改性层,改性层由疏松层、致密层和截面层组成,厚约20μm。微弧氧化处理后的试样在干摩擦小滑动距离下表现出良好的耐磨性。并用SEM,XRD分析了微弧氧化陶瓷层的显微组织、表面形貌和相结构。

A dense ceramic oxide coating with a thickness of 20 μm approximately was directly formed on the surface of AZ31 magnesium alloy through micro-arc oxidation in a electrolytic solution of Na2SiO3-Na2WO4-KOH-Na2 EDTA so as to improve its surface property greatly in this paper. The tribological behavior of the micro-arc oxidized ceramic coatings under dry sliding against SAE52100 steel was evaluated on a ball-on-disc test rig. The AZ31 alloy is characterized by adhesion wear and scuffing under dry sliding against the steel and the results show that the micro-arc oxidated ceramic coatings experience much abated adhesion wear and scuffing under the same testing condition. The micro-arc oxidized ceramic coatings show good friction-reducing and a fair anti-wear ability in dry sliding against the steel. The phase structure and morphology of the carburizing modified layer were analyzed by using SEM and XRD.