铌基合金表面Al-B包埋共渗层的组织及抗氧化性能  

Microstructure and Oxidation Resistance of Al-B Co-Deposition Coatings on Nb-Based Alloy Prepared by Pack Cementation Process

作　　者：秦泽华[1,2] 杨阳[1] 黄祖江[1] 陈泉志[1] 李伟洲[1] 

机构地区：[1]广西大学材料科学与工程学院,广西南宁530004 [2]深圳航空有限责任公司,广东深圳518128

出　　处：《材料保护》2015年第7期15-19,共5页Materials Protection

基　　金：国家自然科学基金(51371059;51001032);广西自然科学基金(2014GXNSF-CA118013;0731013);广西高等学校高水平创新团队项目(第二批);广西自然科学基金创新研究团队项目(2011GXNSFF018001)资助

摘　　要：为提高铌基合金的抗氧化性能,采用包埋共渗法在铌基合金表面于780,860,940℃保温4 h包埋共渗Al-B涂层,采用扫描电镜、X射线衍射仪分析共渗层形貌及结构,采用能谱仪分析其成分;采用高温氧化试验研究渗层的抗高温氧化性能。结果表明:渗层主要形成了Nb Al3,Nb B2和Nb5B6三相,其中在940℃形成的渗层中形成了Al B12相,Al B12在高温下对渗层起到了一定的修复作用;经1 000℃氧化20 h后,渗层保持原始的相组成,并在表面形成由Al Nb O4,Nb O2,B2O3和Al2O3组成的致密混合氧化膜,且与基体结合良好;Al-B共渗层一定程度上改善了铌基合金的抗氧化性能。In order to improve the oxidation resistance of the Nb-based alloy,Al-B co-deposition coatings were prepared on the alloys at 780,860,940 ℃ for 4 h by pack cementation process. The structure and composition of the coatings were analyzed by scanning electron microscopy( SEM)equipped with energy dispersive spectroscopy( EDS) and X-ray diffractometry( XRD),and the high-temperature oxidation resistance of the coatings was studied by high-temperature oxidation tests. Results showed that the coating was mainly composed of NbA l3,NbB2 and Nb5B6 phases,and AlB 12 phase only formed in the coating at 940 ℃ which could repair the coating at high temperature in a certain degree. After oxidation at 1 000 ℃ for 20 h,the Al-B coatings retained the original constituent phases and adense mixed oxide film composed of AlN bO 4,NbO2,B2O3 and Al2O3was formed and adhered to the substrate well. The Al-B co-deposition coating could improve the oxidation resistance of Nb-based alloys at a certain degree.

关 键 词：铌基合金 Al-B共渗涂层 组织结构 抗氧化性能 

分 类 号：TG174.4[金属学及工艺—金属表面处理]