ZL101铸造铝合金微弧氧化陶瓷层的组织和性能

Structure and Performance of Ceramic Coating Deposited on ZL101 Casting Aluminum Alloy by Microarc Oxidation

通过等离子体微弧放电在Al Si铸造铝合金表面沉积出较厚的陶瓷层。用扫描电镜、X射线衍射分析了膜层的形貌、成分和相组成 ,用显微力学探针测定了硬度和弹性模量分布 ,并探讨了陶瓷相的形成机理。陶瓷层主要由α Al2 O3 、γ Al2 O3 和莫来石相组成 ,膜外层还含有大量SiO2 非晶相。膜外层的硅元素主要来自电解液而不是Al Si合金基体。硬度和弹性模量在陶瓷层里分布具有相似性。从表面到内部 ,硬度和弹性模量逐渐增加 。

A ceramic coating was deposited on Al Si alloy by plasma electrolytic discharge. Its morphology, composition and phase component were analyzed using SEM and XRD.The microhardness and elastic modulus of the coating were determined using mechanical properties microprobe. The coating contains mullite, α Al 2O 3 and γ Al 2O 3 phases. Moreover, in the outer layer of the coating, amorphous SiO 2 has a high fraction besides the above phases. The Si element in the coating comes mainly from the electrolyte rather than the Al Si alloy. The curves of hardness and elastic modulus across the coating are similar. From the surface to the interior of the coating, hardness and elastic modulus gradually increase, however they have a maximum value in the inner layer.