脉冲电子束作用下热障涂层微观结构及热循环性能  

Microstructure and Thermal Cycling Behavior of the Surface-modified Thermal Barrier Coatings by High-current Pulsed Electron Beam

作　　者：吴健 关庆丰[1] 蔡杰[2,3] 吕鹏 张从林[1] 李晨 WU Jian;GUAN Qingfeng;CAI Jie;LYU Peng;ZHANG Conglin;LI Chen(School of Materials Science and Engineering,Jiangsu University,Zhenjiang 212013;Institute of AdvancedManufacturing and Modern Equipment Technical,Jiangsu University,Zhenjiang 212013;School of Mechanical Engineering,Jiangsu University,Zhenjiang 212013)

机构地区：[1]江苏大学材料科学与工程学院,镇江212013 [2]江苏大学先进制造与现代装备技术工程研究院,镇江212013 [3]江苏大学机械工程学院,镇江212013

出　　处：《材料导报》2018年第13期2202-2207,共6页Materials Reports

基　　金：国家自然科学基金(51601072;U1233111);江苏省自然科学基金青年基金(BK20160530);中国博士后科学基金(2016M601730);江苏省博士后基金(1601007C);江苏大学高级人才科研启动基金(15JDG149);江苏大学青年英才培育计划

摘　　要：利用强流脉冲电子束(HCPEB)技术对大气等离子喷涂(APS)技术制备的热障涂层(TBCs)进行表面处理,探究HCPEB辐照对TBCs微观结构以及热循环性能的影响。热循环实验采用950℃炉温加热并随后水淬。采用X射线衍射,扫描电子显微镜详细分析了辐照前后涂层表面微观结构及相组成。X射线分析结果表明,HCPEB辐照后陶瓷层中单斜相m相含量降低;此外,衍射峰发生宽化及偏移说明伴随有晶粒细化以及残余应力产生。微观结构观察表明,HCPEB辐照后热喷涂缺陷消失,涂层发生重熔,涂层表面粗糙度降低,且重熔层内部有网状垂直微裂纹以及柱状晶产生。热循环实验表明,250次热循环后原始涂层发生整体剥落,涂层失效;而HCPEB辐照后涂层并未出现明显的剥落迹象,仅存在水平裂纹的扩展,涂层的热循环寿命明显提高。High-current pulsed electron beam（HCPEB）treatment was conducted on thermal barrier coatings（TBCs）prepared by air plasma sprayed（APS）technology.The effects of HCPEB irradiation on the microstructure and thermal cycling behavior of TBCs were investigated.The thermal cycling test was carried out by using a muffle furnace,and each cycle consisted of holding at950 ℃in air and cooling by water quenching.The microstructure and phase composition of the coatings before and after HCPEB irradiation were characterized by scanning electron microscopy（SEM）and X-ray diffraction（XRD）.The XRD results revealed that the content of monoclinic（m）phase in the yttria stabilized zirconia（YSZ）topcoat was reduced after HCPEB irradiation.Besides,the width of peaks became wider and peak locations slightly shifted,which indicated the grain refinement and residual stress generation.The remelting of the coating surface,the elimination of thermal sprayed defects,the reduced surface roughness,as well as a continuous micro-crack network perpendicular to the surface and columnar grains in the remelted layer,could be observed by SEM for the HCPEB irradiated YSZ topcoat.Thermal cycling test results confirmed the failure of the initial YSZ coating after 250 cycles,as the overall spalling occurred.Contrastively,no obvious signs of spallation appeared for the irradiated coating,and only the propagation of horizontal cracks can be observed.Our experiment validated the higher thermal cycling resistance of the HCPEB-TBCs.

关 键 词：YSZ陶瓷层 强流脉冲电子束 微观结构 热循环性能 

分 类 号：TB321[一般工业技术—材料科学与工程]