镁合金表面激光熔覆Al_2 O_3陶瓷涂层组织分析及数值模拟  

Microstructure analysis and numerical simulation of laser cladding AL_2O_3 ceramic coating on magnesium alloy

作　　者：高亚丽[1] 王存山[1] 姚曼[2] 刘红宾[1] 

机构地区：[1]大连理工大学三束材料改性国家重点实验室,辽宁大连116023 [2]大连理工大学材料学院,辽宁大连116023

出　　处：《应用激光》2006年第6期393-397,共5页Applied Laser

摘　　要：本文采用激光重熔等离子涂层的方法在AZ91HP镁合金上制备Al_2O_3陶瓷涂层,在实验和理论基础上利用有限差分方法对激光重熔过程中的温度场进行模拟。研究结果表明,在激光作用下,相应于不同的温度范围涂层形成了熔凝区(柱状晶)、烧结区(团絮状组织)和残留等离子区(层状结构)。与激光功率相比,激光扫描速度对涂层温度分布影响较大。Al2O3 ceramic coating was prepared on AZ91HP magnesium alloy by laser remelting the plasma - sprayed coating. On the basic of the experiment and theory, the temperature field of the laser remelting process was simulated with the finite difference method. The results showed that the coating formed the melted zone （ columnar grains）, the sintered zone （ nodular structure） and remained plasma- sprayed zone （lamellar structure） according to the different temperature range. Compared with the laser power, the scanning speed had great influence on the temperature distribution of the coating, and also had significant influence on the thickness of the remained plasma - sprayed coating and the solidified structure of Al - Si transition layer.

关 键 词：AZ91HP镁合金 AL2O3陶瓷涂层 等离子喷涂 激光重熔 

分 类 号：TG174.453[金属学及工艺—金属表面处理]