激光熔覆原位合成αFe(Al)/Fe_3Al涂层的研究  

Investigation on In-Situ Synthesizing α-Fe(Al)/Fe_3Al Coating by Laser Cladding

作　　者：张来启[1] 陈光南[2] 孙祖庆[1] 杨王玥[1] 

机构地区：[1]北京科技大学新金属材料国家重点实验室,北京100083 [2]中国科学院力学研究所,北京100080

出　　处：《金属热处理》2004年第6期1-4,共4页Heat Treatment of Metals

基　　金：国家自然科学基金重点项目 ( 5 983 62 2 0 )

摘　　要：通过寻求工艺参数与Fe 2 8% (at)Al粉末的最佳匹配 ,利用激光熔覆和复合材料原位合成技术 ,制备了熔覆质量好的α Fe(Al) /Fe3Al涂层。该熔覆层为α Fe(Al)固溶体胞状组织基体上分布着黑色DO3结构Fe3Al质点 ,多数质点分布在晶界上 ,颗粒尺寸为 (10 0～ 30 0 )nm。EDAX线扫描结果表明 ,Al、Fe在整个涂层中分布比较均匀 ,无宏观偏析 ;Al、Fe成分在近界面及界面处缓慢过渡 ,涂层和基体发生互扩散 ,为冶金结合。熔覆层的显微硬度为 6 39HV0 2 ,比基体高 2倍 ,多道搭接处理对熔覆层的硬度影响不大。The α-Fe(Al)/Fe_3Al coating with good cladding quality was fabricated by seeking an optimal match of laser process parameters for the composition of the Fe-28%(at) Al mixture by means of the combination of the laser cladding technique and the in-situ synthesizing technique of composites.It has been observed that this clad coating is the black particulates of DO_3-type Fe_3Al,with the size of (100～300)nm,distributed within the matrix of the cellular α-Fe(Al) solid solution,and mostly at grain boundaries.The composition analysis results of the EDAX line scanning show that the content distributions of Fe and Al are relatively even along the whole coating from the macroscopical viewpoint,free of macrosegregation,and that the compositions of Fe and Al gradually transit by inches near and at the interfaces between the coating and the substrate,illustrating that the atoms of constituent elements of the coating and the substrate diffuse each other,and the coating is metallurgically bonded to the substrate.It has been found that the hardness of the clad coating is 639HV0.2,twice higher than that of the substrate,and that the overlapping treatment has few influence on hardness of the coating.

关 键 词：激光熔覆 原位合成 Fe—Al金属间化合物 铁铝化物 涂层 

分 类 号：TG156.99[金属学及工艺—热处理]