摘要
运用激光熔覆技术在AISI1045钢表面制备了30vol-%SiCp/Ni-Cr-B-Si-C涂层。SEM和TEM观察分析表明:SiCp在熔覆过程中完全溶解;涂层结合区组织为共晶结构;涂层组织由初生石墨球G,分布在γ-Ni固溶体枝晶中的M23(C,B)6细小网状树枝晶以及少量Ni+Ni3(B,Si)层片状共晶组成;Si在Ni固溶体中的固溶度显著增大,高达14.41wt-%;M23(C,B)6含有高密度堆垛层错;Ni3(B,Si)相具有长周期结构。
The laser surface cladding technique was used to form a 30vol % SiCp/Ni Cr B Si C composite coating on the AISI1045 steel substrate. The microstructure of the coating was investigated by SEM and TEM. SiCp had completely dissolved in the Ni based alloy during the laser processing. The bonding zone between the coating and the substrate had an eutectic structure, characterized by directional solidification and enrichment in Fe. The clad layer had a very fine microstructure which consisted of primary graphite G in the upper part of the Clad, closely spaced M 23 (C,B) 6 dendrites in γ Ni solid solution, and a small amount of lamellar eutectic Ni+Ni 3(B,Si). TEM EDX compositional analysis showed a marked extension in solid solubility of Si in Ni solid solution because of the high cooling rate. M 23 (C,B) 6 contains a high density of stacking faults. The microdiffraction pattern revealed a long periodicity of Ni 3(B,Si).
出处
《中国激光》
EI
CAS
CSCD
北大核心
1999年第1期80-84,共5页
Chinese Journal of Lasers
基金
金属精密热加工国防科技重点实验室资助项目
关键词
激光熔覆
合金涂层
微观组织
laser cladding, SiCp/Ni based alloy coating, microstructure