合金元素对铁基激光熔覆涂层显微组织和相结构形态的影响  

Effect of alloy elements on microstructure and phase structure of laser cladding Fe-based coatings

作　　者：聂斌英[1] 姚成武[2] 

机构地区：[1]宜春学院化学与生物工程学院,宜春336000 [2]上海交通大学上海市激光制造与材料改性重点实验室,上海200240

出　　处：《焊接学报》2013年第1期85-88,117,共4页Transactions of The China Welding Institution

基　　金：洁净钢工艺仿真与连接界面结构及性能表征研究(2010-CB735809)

摘　　要：利用CO2激光在45钢表面熔覆制备铁基合金涂层,研究4种合金元素对改变涂层组织形态以及枝晶间碳化物形状的影响规律.结果表明,随着V,Nb,Ti元素和稀土氧化物CeO的依次加入,熔覆涂层原柱状晶形态逐渐改变为柱状树枝晶,最后转变为无明显柱状晶方向性的树枝晶;在激光熔覆涂层中,同时添加V,Nb元素,涂层枝晶间的连续长条状碳化物被打断成块状;同时添加V,Nb,Ti元素和稀土氧化物CeO,涂层枝晶间的碳化物被球化.通过改善涂层树枝晶组织形态以及球化枝晶间碳化物,涂层的抗拉强度和断后伸长率明显提高,涂层的强韧性显著增加.Four types of Fe-based alloys were fabricated on 45 carbon steel substrate by CO2 laser surface cladding,and the effect of alloy elements on the microstructure and carbides of the coatings was investigated.With the increasing of the elements V,Nb,Ti,CeO in turn,the structure of the coating was transformed from the columnar crystal to columnar dendrites,and finally to the dendrite.With the simultaneous addition of the two elements V,Nb in the coating,the long strip carbides in the interdendritic region split into blocky carbides.At last,the carbides in the interdendritic region of the coating can be refined and spheroidized by adding elements V,Nb,Ti,CeO.The tensile test results showed that the tensile strength and elongation rate of the coating with dendritic structure and spheroidized carbides in the interdendritic region increased greatly,and the coating had high strength-toughness properties.

关 键 词：激光熔覆 铁基涂层 合金元素 显微组织形态 碳化物 

分 类 号：TG401[金属学及工艺—焊接]