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

摘要:

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。

Abstract:

A rapidly solidified TiC/FeAl composite coating was fabricated on substrate of 1Cr18Ni9Ti stainless steel by 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 of 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.