摘要
利用CO2激光器在45#钢基体上成功制备了原位生成NbC颗粒增强的镍基合金涂层,涂层与基体呈现良好的冶金结合,无裂纹气孔等缺陷。涂层组织主要有γ-Ni树枝晶,枝晶间大量的共晶组织,M2(3CB)6型碳化物和弥散分布的原位生成的NbC颗粒组成。带核的NbC颗粒是以为完全溶解的Nb为核心在其上长大的。由于原位生成NbC颗粒在复合涂层中的均匀分布,使涂层的平均显微硬度高达HV0.2 750,比纯Ni45合金涂层提高了约36%。
The in situ synthesized NbC particles reinforced Ni-based alloy composite coating has been successfully prepared on 1045 steel substrate by laser cladding. The coating is free of pores and cracks with excellent bonding between the coating and the substrate. The microstructure of the coating is mainly composed of 7-Ni dendrite, a large amount of interdendritic eutectics, M23 （CB）6 type carbides and dispersed NbC particles. The growth mechanism of the NbC particles with cores is nucleation-growth and the un-melted niobium may act as the nucleation core for NbC. Compared to the pure Ni-based alloy coating, the hardness of the composite coating is increased about 36 %, giving a high average hardness of approximate HV0.2750. This is attributed to the presence of in situ Synthesized NbC particles and their well distribution in the coating.
出处
《应用激光》
CSCD
北大核心
2012年第6期459-463,共5页
Applied Laser
基金
浙江省教育厅资助项目(项目编号:Y201120010)
