摘要
在45#钢基底上进行了铁基合金加Nb2O5的多道搭接激光熔覆实验。利用金相显微镜和扫描电镜观察熔覆层横断面的显微组织,进行了EDS能谱分析,并测试了熔覆层的硬度。结果表明:由于搭接的过程中激光的二次加热,促进了共晶体中的Ni的硅化物的重溶,相邻两道的搭接区的组织与其他区域的树枝状枝晶组织明显不同,为微小的颗状晶粒均匀地分布在奥氏体基体上。搭接区的硬度与未受搭接影响的区域基本一致,只是在熔覆层的接近表面部位硬度分布更加均匀。
The experiments of laser cladding of Fe - based composite alloy powder with Nb205 on steel 45 were carried. The structural observation on the cross - section of laser coatings by a metallurgical microscope and a scanning electron microscope （SEM） were performed. 3he alloying component analysis in minute region by energy spectrum analysis （EDS） was also made.The hardness was measured too. The result is that some of the branch - like dendritics composed of Ni and Si in the overlapped area are dissolved in γ （ Fe - Ni） solid solution during the reheating process of laser, so the structure of the overlapped area is much different from other areas made of dendritic eutectics. It shows that little particles about several μm are uniformly distributed among γ（ Fe - Ni） solid solution in overlapped area. Except the hardness distribution of the overlapped area in the upper part of coatings is more even, the hardness of overlapped area is nearly consistent with other parts.
出处
《激光杂志》
CAS
CSCD
北大核心
2007年第5期64-65,共2页
Laser Journal
关键词
激光熔覆
多道搭接
组织
硬度
laser cladding
over - lapped
mierostructure
wear resistance
