激光熔覆原位析出Ni-Fe-Ti-B复合涂层组织结构研究  

Research on microstructure of Ni-Fe-Ti-B composite coating in-situ separating out by laser cladding

作　　者：张维平[1] 刘硕[1] 

机构地区：[1]大连理工大学材料工程系,辽宁大连116024

出　　处：《大连理工大学学报》2005年第3期351-356,共6页Journal of Dalian University of Technology

基　　金：国家自然科学基金资助项目(59701001).

摘　　要：选用合适的激光工艺参数及涂层成分,在45#钢基体表面得到了激光熔覆原位析出的Ni-Fe-Ti-B复合材料涂层.涂层中的粘结金属基体为γ-(Ni,Fe)和Nihcp,原位弥散析出相为呈现出颗粒状、细条状等分布的稳定相TiB2、Ni4B3及亚稳定相Ni2B、(Fe,Ni)3B型化合物.前两者已经细化成为纳米晶,而后两者晶粒度相对较粗.γ-(Ni,Fe)是稳定的Ni、Fe固溶体,而Nihcp形成于基体金属内部的堆垛层错作用;原位析出相产生于激光熔覆过程中涂层表面发生的原位燃烧反应或合金系快速凝固过程中的低熔点共晶作用.在基体与析出相的界面上存在高密度位错堆积,从而引起基体金属亚结构细化.In-situ separating out Ni-Fe-Ti-B composite coating has been fabricated on 45# steel surface by laser cladding with optimal laser parameters and coating compositions. The bonding metal matrix is γ-(Ni, Fe) and Nihcp, and the in-situ separating out phases are stable TiB2, Ni4B3 and metastable Ni2B, (Fe, Ni)3B type compounds with the shape of granular and thin strip. The former two are fine enough to present nano-crystalline while the latter two are relatively coarse. γ-(Ni, Fe) is stable solid solution of Ni and Fe, whereas the formation of Nihcp contributes to the stacking fault in the matrix. The in-situ separating out phases are produced from the combustion reaction in the coating surface or the low melting point eutectic reaction in the alloy system during laser cladding and the rapid solidification. High density dislocation pile-up lies in the interface of the matrix and the second phase, which induces the sub-structure fining of the matrix.

关 键 词：激光熔覆 原位析出 结构研究 涂层组织 复合材料涂层 基体金属 45^#钢 低熔点共晶 析出相 工艺参数 金属基体 基体表面 TiB2 Ni2B 堆垛层错 凝固过程 燃烧反应 涂层表面 稳定相 颗粒状 纳米晶 化合物 晶粒度 固溶体 高密度 

分 类 号：TG156.99[金属学及工艺—热处理] TB331[金属学及工艺—金属学]