摘要
为了研究燃气轮机叶片材料K444铸造镍基高温合金的高温氧化性能,研究了K444铸造镍基高温合金800℃及850℃恒温氧化动力学及氧化机制.采用x-射线衍射仪、扫描电子显微镜及能谱仪分析了K444合金氧化产物、氧化膜形貌及成分.结果表明:在实验条件下K444合金氧化动力学遵循抛物线规律.在高温氧化期间,K444合金表面氧化膜无明显剥落.氧化膜主要由Cr2O3组成,含有少量的NiCr2O4及TiO2.氧化膜呈多层结构:外层较薄,膜质疏松,孔隙较多,是以TiO2为主的不连续氧化物膜层;中间层是以Cr2O3为主的连续致密保护性氧化物膜层,其中含有少量的NiCr2O4及TiO2;内氧化层以Al2O3为主.
In order to identify the high-temperature oxidation perfromance of cast nickel-base superalloy K444 used as gas turbine blade material,the isothermal oxidation kinetic and oxidation mechanism of the K444 alloy at 800℃and 850℃were investigated.X-ray diffractometer,scanning electron microscope and energy dispersive spectrdmeter were used to analyze the oxidation products as well as the morphology and composition of oxide on cast nickel-base superalloy K444.The results show that the oxidation kinetic curves of the alloy at 800 ℃and 850℃obey the parabolic law,and almost no oxide spallation is observed.The oxide scale mainly consists of Cr2 O3 with small amount of NiCr2 O4 and TiO2,and has the multilayer structure.The outmost thin layer is porous and mainly contains non-protective TiO2.The protective Cr2 O3 layer with a certain amount of NiCr2 O4 and TiO2 is the main layer of the scale.The internal oxide layer is mainly composed of Al2 O3.
出处
《沈阳工业大学学报》
EI
CAS
2010年第2期136-140,共5页
Journal of Shenyang University of Technology
基金
沈阳市科技局攻关项目(108149-2-00
1091242-6-00)
关键词
镍基高温合金
高温氧化
氧化动力学
氧化膜
氧化机理
抗氧化性能
组织结构
内氧化
nickel-based superalloy
high-temperature oxidation
oxidation kinetics
oxide scale
oxidation mechanism
oxidation resistance
microstructure
internal oxidation
