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针对传统热障涂层陶瓷面层与金属基体结合强度较低的问题,提出ZrO_2颗粒增强金属基热障功能复合材料层结构,并采用激光熔注技术在Ti-6Al-4V基体表面实现制备.研究了复合材料层的物相组成及微观组织结构,测试了其热导率,结果表明:团聚ZrO_2颗粒在熔池中受到热应力作用与钛熔体的固溶分解作用,产生自外向内的离散行为;激光熔注的工艺特性导致复合材料层的不同区域出现明显的形貌特征差异,30～50μm ZrO_2颗粒体积分数沿深度方向梯度分布,1～3μm ZrO_(2-x)小颗粒在底部分布更为密集;复合材料层的有效热导率随着ZrO_2体积分数的增加而显著降低,最低降至3.4 W/(m·K).
Aiming at the problem of low bond strength between traditional thermal barrier coating and metal substrate, ZrO_2 particle reinforced metal-based thermal barrier composite was proposed. The surface of Ti-6Al-4V substrate was prepared by laser melting technology. The phase composition and microstructure of the composites were studied and their thermal conductivities were tested. The results showed that the agglomerated ZrO 2 particles were subjected to thermal stress in the melt pool and to the solution and solid solution decomposition of titanium melt, Discrete behavior. The laser melting process results in obvious morphological differences in the different regions of the composite layer. The volume fraction of 30-50μm ZrO 2 particles distributes along the depth direction, while the 1-3μm ZrO 2-x particles at the bottom The density of the composite material layer is significantly decreased with the increase of the volume fraction of ZrO 2, and the minimum is 3.4 W / (m · K).