激光熔覆法制备ZrO_2-Y_2O_3涂层的显微组织与性能研究  

Microstructure and Properties of ZrO_2-Y_2O_3 Coating Prepared by Laser Cladding

作　　者：黄旺华[1,2] 李崇桂[1,2] 潘斌[1,2] 王恩廷[1,2] 宋晓航 封小松 

机构地区：[1]上海工程技术大学材料工程学院,上海201620 [2]高强激光智能加工装备关键技术产学研开发中心,上海201620 [3]上海航天设备制造总厂,上海200245

出　　处：《硅酸盐通报》2016年第4期1192-1197,共6页Bulletin of the Chinese Ceramic Society

基　　金：国家自然科学基金(51402189);国家自然科学基金(51305272);上海工程技术大学研究生创新项目(14KY0506);上海市自然科学基金项目(13ZR1455300);上海市教育委员会科研创新项目(13YZ114);上海航天科技创新基金项目(SAST201207)

摘　　要：采用预制粉末式激光熔覆法在钛合金（Ti-6Al-4V）表面制备了纳米ZrO_2-8%Y_2O_3涂层,利用X射线衍射仪（XRD）、扫描电镜（SEM）和光学显微镜（OM）对涂层的相组成及组织结构进行分析,同时分析了涂层的显微硬度分布情况。结果表明：在一定功率范围内,涂层气孔随激光功率增大而逐渐减少,裂纹随激光功率增大而增多;ZrO_2陶瓷涂层与基体间结合良好,熔覆层微观组织结构主要以细小的树枝晶形态存在。在不同区域表现出不同的组织特征,靠近表面处晶体尺寸相对较小,呈柱状整齐排列在熔覆层表层区域;熔覆层中部主要包含块状晶及少量树枝晶;熔覆层底部主要为树枝晶,其一次晶轴方向沿垂直于涂层截面方向生长;熔覆层主要由四方相（t相）ZrO_2和立方相（c相）ZrO_2组成;熔覆层平均硬度达到1000-1300 HV0.2,约为基材硬度的3.5倍。The preparation of ZrO_2-8% Y_2O_3 coating were studied on the surface of Ti-6Al-4V alloy by laser cladding with preset powder. The phase constituents and microstructure of the coating were analyzed by XRD,SEM and OM,and the microhardness of the coating was also measured. The results show that coating porosity increases with laser power and gradually reduce,crack increases with laser power and increase; ZrO_2 ceramic bonding between coating and substrate is good,the cladding layer microstructure mainly small dendrites,In different regions show different organizational characteristics,near the free surface of the crystal size is relatively small,columnar neatly arranged in the surface region of the cladding layer. Central cladding layer mainly includes the massive crystal and a small amount of dendrites. At the bottom of the cladding layer are mainly dendrites,one major axis direction along thedirection perpendicular to the coating section. The coating consists of t-ZrO_2 and c-ZrO_2phase; The average hardness of the cladding layer is about 3. 5 times of the substrate.

关 键 词：激光熔覆 氧化锆 微观组织 显微硬度 

分 类 号：TQ175[化学工程—硅酸盐工业]