火焰喷涂镍/石墨封严涂层热稳定性研究  

Thermal stability of Ni/graphite abradable sealing coatings by flame spraying

作　　者：贾鹏[1] 王志平[1] 韦宁[2] 张彦飞[2] 

机构地区：[1]中国民航大学 天津市民用航空器适航与维修重点实验室,300300 [2]中航工业哈尔滨东安发动机集团有限公司,150066

出　　处：《焊接》2012年第5期65-68,72,共4页Welding & Joining

摘　　要：采用火焰喷涂工艺制备了镍/石墨封严涂层,在500℃氧化性气氛中进行热稳定性试验。涂层力学测试结果表明:热稳定后涂层硬度上升,结合强度下降;随着热稳定时间的延长,涂层的硬度和结合强度趋于稳定。XRD、EDS和涂层微观组织分析发现:涂层热稳定300 h后,石墨生成气体脱离涂层,造成镍基骨架暴露在高温氧化性气氛中发生氧化反应,导致涂层硬度上升,部分生成于骨架内部的条纹状氧化物割裂了基体的连续性,造成涂层结合强度下降。Ni/graphite abradable sealing coatings were deposited by flame spraying,and the thermal stability was investigated at high-temperature oxidizing atmosphere.The results of mechanical tests show that the bonding strength increases and hardness decreases,and then they tend to the stable values.XRD,EDS,microstructure analysis show that Ni was oxidized as Ni exposed to air because graphite is ablated after 300 h thermal stability.The oxidation caused the increase in hardness,and the stripe oxidation makes the bonding strength be decreased.

关 键 词：镍/石墨封严涂层 热稳定 火焰喷涂 涂层性能 

分 类 号：TG174.442[金属学及工艺—金属表面处理]