镁合金表面冷喷涂铝涂层的热处理研究  

Heat Treatment of Cold Spray Aluminum Coating on Magnesium Substrates

作　　者：卜恒勇[1,2] 卢晨[1] 

机构地区：[1]上海交通大学轻合金精密成型国家工程研究中心,上海200240 [2]渥太华大学机械工程系冷喷涂实验室

出　　处：《金属功能材料》2011年第4期26-31,共6页Metallic Functional Materials

摘　　要：使用冷喷涂方法在铸态AZ91D镁合金基体上沉积了纯Al涂层,所得涂层组织致密,厚度均匀,与基体结合良好,孔隙率小于1%。随后用机械减薄的方法使Al涂层的厚度减薄到135μm,对减薄后的试样在真空加热炉中分别进行了400℃×20 h和400℃×40 h的热处理。结果显示随着保温时间的延长,Al涂层全部转化为较高硬度和较好耐蚀性的Mg17Al12(β相)和Al3Mg2(γ相)金属间化合物,其整体厚度达到263μm,远超过热处理前Al涂层的厚度。Commercial pure aluminum powders were deposited onto as-cast AZ91D magnesium alloy substrate and formed a coating by using cold spray technology.The coating thickness was uniform and have a good bonding with the substrate,it have a higher density with a porosity content less than 1%.The Al coatings were annealed at 400 ℃ for 20 h and 40 h after milled to around 135 μm.The results show that as the holding time increased,the Al coatings all transformed to Mg17Al12 and Al3Mg2 intermetallics,which perform higher hardness and better corrosion resistance compared to Mg substrates.These intermetallics have a total thickness of 263 μm which is much more higher than Al coatings before annealing.

关 键 词：镁合金 冷喷涂 铝涂层 金属间化合物 热处理 

分 类 号：TG174.44[金属学及工艺—金属表面处理] TG156[金属学及工艺—金属学]