摘要
为了提高铝合金的综合性能,采用等离子喷涂技术在AZ31B镁合金表面沉积氧化钇部分稳定二氧化锆(YSZ)涂层,并采用二氧化碳激光器对涂层表面进行重熔处理,利用X射线衍射仪、扫描电镜及三维激光成像显微镜研究了重熔激光功率对涂层物相组成、组织结构及表面形态的影响规律。结果表明:YSZ涂层在激光表面重熔过程中保持了相结构的稳定性,即喷涂态及激光重熔后的涂层均由非转变型的四方相组成;随激光功率的增大,重熔区厚度不断增加,且喷涂态涂层的层状组织结构在激光重熔后消失,气孔率降低;在激光处理过程中,产生了大量的内应力,导致纵向(垂直于涂层表面)裂纹的萌生及扩展;涂层表面粗糙度随激光功率的增加而不断降低,并且在功率低于400 W时下降更明显。
In order to improve the comprehensive properties of Al alloy,the yttrium oxide partially stabilized zirconia(YSZ) coating was deposited on AZ31 B magnesium alloy by plasma spraying method,and then carbon dioxide laser was utilized to remelt the coating surface.The X-ray diffraction(XRD),scanning electron microscopy(SEM) and 3D laser scanning microscopy were used to analyze the influences of laser remelting power on the phase composition,microstructure and surface morphology of coatings.Results showed that YSZ coating kept stable phase structure during laser surface remelting process,and both the as- sprayed and laser remelted coatings were composed of non-transformable tetragonal phase.As the laser power increased,the thickness of remelted zone increased.In addition,after laser remelting,the lamellar structure of as- sprayed coating disappeared,and porosity of coating declined.During laser treatment process,massive residual stress was generated,leading to the emerging and spreading of longitudinal cracks(perpendicular to coating surface).With the increase of laser power,the roughness of coating decreased gradually,especially when the power was below 400 W.
出处
《材料保护》
CAS
CSCD
北大核心
2016年第12期1-4,共4页
Materials Protection
基金
国家自然科学基金(51202211
51202187)资助
关键词
AZ31B镁合金
YSZ涂层
等离子喷涂
激光重熔
结构
表面粗糙度
AZ31B magnesium alloy
yttria-stabilized zirconia coating
plasma spraying
laser remelting
structure
surface roughness
