摘要
在 TC4合金表面进行了激光熔覆 Ni Cr BSi涂层的试验 ,结果表明 ,激光熔覆层在微观结构上存在熔覆区、结合区和基体热影响区三个区域。熔覆区的组织是在初晶 γ Ni和 γ Ni、Ni3B、硅化物组成的多元共晶基底上分布着 Ti B2 、Ti C、M2 3( CB) 6等颗粒增强相。结合区是熔覆材料 Ni基合金和基体钛合金的混熔区 ,呈定向凝固特征。基体热影响区为针状马氏体组织。激光熔覆层的耐磨性能比时效硬化的钛合金显著提高 ,磨损机制是剥层磨损和磨粒磨损。
Laser cladding of NiCrBSi powers on TC4 alloy substrate was performed. Results show that the laser clad layer is devided into the clad,the binding and the heataffected zones. In the clad zone, fine particles of TiB 2, TiC and M 23 (CB) 6 are distributed in the matrix of the primary γNi and the multiple eutectic consisting of γNi,Ni 3B and silicides. The binding zone is a mixture of melted Nibase and Tibase alloys,and possesses a characteristic of directional crystallization. The heataffected zone has an acicular martensitic structure. Compared to agehardening titanium alloys,the wear resistance of laser clad layer is improved remarkably. The mechanism of wearing of clad layer is a mixed type of slight peelingoff and abrasive wearing.
出处
《应用激光》
CSCD
北大核心
2000年第6期261-263,260,共4页
Applied Laser
关键词
钛合金
激光熔覆
组织
耐磨性能
Titanium alloys, Laser cladding, Microstructure, Wear resista`
