AZ91D镁合金激光熔覆Al+Al_2O_3涂层的界面特征

Interface Characterization of Laser Cladding Al+Al_2O_3 Coating on AZ91D Surface

在AZ91D镁合金表面激光熔覆Al+Al2O3粉末制得了复合涂层。用扫描电镜、高分辨透射电镜和原子力显微镜对涂层与AZ91D镁合金基体界面结合区生长形态和特征以及涂层中Al2O3粒子的分布进行了观察,用能谱仪对界面结合区的元素线扫描,用X射线衍射分析确定了涂层及基体中的相组成。结果显示,涂层中Al2O3粒子的分布是均匀的,结合区的生长形态为独特的平行树枝晶,其组织形态受激光工艺参数的影响。

The laser cladding Al＋Al2O3 coating on AZ91D surface was prepared. The characterization,the growth morphology the interface zone and the distribution of Al2O3 particles in the cladding layer were observed by AFM, HRTEM and SEM.The element line scanning analyses on the interface zone were carried out with energy-dispersive spectrum. The phases in the laser cladding layer and the substrate of AZ91D were identified by XRD. The results show that the distribution of the Al2O3 particles is homogeneous in the cladding layer; the growth morphology of the boundary zone is a unique parallel-branching feature, and the microstructure is affected by laser parameters.