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.
出处
《材料保护》
CAS
CSCD
北大核心
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