激光熔覆TiC/FeAl复合材料涂层显微组织及初生TiC生长机制研究

Microstructure of Laser Clad TiC/FeAl Composite Coating and Growth Mechanism of Primary TiC Carbide

利用激光熔覆技术在1Cr18Ni9Ti奥氏体不锈钢基体上制得了以TiC为增强相、以FeAl金属间化合物为基体的快速凝固TiC/FeAl复合材料涂层,分析了该涂层的显微组织及初生TiC的生长形态和生长机制。研究结果表明,激光熔覆TiC/FeAl快速凝固复合材料涂层主要由初生TiC碳化物、初生FeAl树枝晶和枝晶间少量的FeAl/TiC共晶组成,初生TiC具有独特的径向辐射分枝小面枝晶团簇状生长形态,其生长机制为侧向生长。

A rapidly solidified TiC/FeAl composite coating was fabricated on substrate of 1Cr18Ni9Ti stainless steel b laser cladding. The microstructure of, composite coating, the growth morphology and growth mechanism of primary TiC carbide were investigated. Results show that the laser clad coating has a microstructure consisting of primary TiC, primary dendritic FeAl and small amount if interdendritic FeAl/TiC eutectic. The primary TiC carbide has an unique growth morphology of radial-branching faceted dendritic colony, and its growth mechanism is still lateral growth.