摘要
为提高TC4合金的抗高温氧化性能。采用在900,940和980℃扩散渗2 h的方法在TC4合金表面制备了Y改性的铝化物渗层,并通过扫描电子显微镜、X射线衍射仪及能谱仪分析了渗层的结构及相组成,研究了渗层在1000℃时的抗氧化性能,讨论了其氧化机制。结果表明:不同温度所制备的渗层主要组成相均为Al3Ti,此外在900℃制备渗层中含有少量的Al23V6,在940,980℃制备渗层中分别检测到了Al2Ti3及Al2Ti相;渗剂中添加Y能够降低涂层的内应力,抑制渗层中裂纹的产生。940℃共渗2 h制备的Y改性Al化物渗层在1000℃氧化50 h后表面形成了致密的Al2O3氧化膜,显著的提高了TC4合金的抗高温氧化性能。
The surfaces of TC4 alloy,an advanced aerospace material,were modified with yttria-doped aluminide coatings,synthesized by pack cementation with the agent of 15 Al-2 Y2O3-6 NH4Cl-71 Al2O3(wt%)for oxidation-resistance enhancement.The influence of the yttria-doping on the microstructures,phase-structures and oxidation resistance was investigated with X-ray diffraction,scanning electron microscopy and energy dispersive spectroscopy.The results show that the yttria-doping had a major impact.To be specific,the yttria-doping significantly reduced the residual stress,increased the interfacial adhesion and inhibited crack formation.Al3Ti phase dominated the modified surfaces,and small amounts of Al23V6,Al2Ti3 and Al2Ti phases were correlated to a synthesis temperature of 900℃,940℃and 980℃,respectively.Oxidized at 1,000℃for 50 h,the compact Al2O3-coatings formed,on the TC4 alloy modified at 940℃for 2 h,and considerably enhanced the oxidation resistance of TC4 alloy.
作者
李涌泉
秦春
蒋亮
耿桂宏
Li Yongquan;Qin Chun;Jiang Liang;Geng Guihong(School of Material Science&Enginering,North Minzu University,Yinchuan 750021,China)
出处
《真空科学与技术学报》
EI
CAS
CSCD
北大核心
2020年第4期332-336,共5页
Chinese Journal of Vacuum Science and Technology
基金
宁夏高等学校科学技术研究项目(优青)(NGY2018-148)
粉体材料与特种陶瓷重点实验室开放基金课题(No:1805)
国家自然科学基金项目(51961003)。
关键词
TC4合金
Al-Y渗层
显微组织
抗高温氧化
扩散渗
TC4 alloy
Al-Y coating
Microstructure
High temperature oxidation resistance
Pack cementation
