摘要
目的提高物理气相沉积Cr/Al涂层与基材锆合金的结合强度,减少涂层表面微观缺陷及内应力。方法采用多弧离子镀及磁控溅射技术在锆合金表面溅射Cr/Al涂层,并将涂层试样分别置于600、800℃保护气氛炉中热处理30 min。利用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、X射线光电子能谱仪(EDS)及光学显微镜(OM),分析了Cr/Al涂层热处理前后相组成、表面形貌、截面形貌、元素成分变化及涂层剪切后的剥落形貌。利用弹簧拉压试验机,测试了未处理涂层、600℃和800℃热处理涂层试样与基材锆合金的结合强度。结果 600、800℃热处理涂层相比未处理涂层,表面更加平滑,表面孔隙及微观缺陷较少,但与基材锆合金的结合强度并没有明显变化,未热处理涂层、600℃热处理涂层、800℃热处理涂层与基材锆合金的结合强度分别为44.07、44.12、44.08 MPa。结论热处理后,涂层出现Al Cr2、Al8Cr5、Al9Cr17、Al9Cr4、Al86Cr14等多种Cr-Al合金相,有利于涂层表面孔隙及大颗粒等缺陷的减少。但热处理前后,涂层与基材的结合强度未发生明显变化。
The work aims to improve bonding strength of Cr/Al coatings prepared in the method of physical vapor deposition（PVD） and the substrate zirconium alloy, so as to reduce the internal stress and microdefects on the coatings. The Cr/Al coatings were sputtered on the surface of zirconium alloy by multi-arc ion plating and magnetron sputtering. The coating samples were placed and heat treated in 600 ℃and 800 ℃protective atmosphere oven for 30 min. Phase composition, surface morphology, cross-sectional morphology and element compositional variation of Cr/Al coatings before and after heat treatment, and peeling morphology of the sheared Cr/Al coatings were analyzed with X-ray diffractometer（XRD）, scanning electron microscopy（SEM）, X-ray photoelectron spectroscopy（EDS） and optical microscopy（OM）. Bonding strength between untreatedcoating, coating samples heated treated at 600 ℃ and 800 ℃, and the substrate zirconium alloy were tested with spring tension and compression testing machine. Compared with untreated coating, the coating surfaces heat treated at 600 ℃ and 800 ℃ featured in smoother surface, less surface pores and microdefects. However, the bonding strength between the coatings and the substrate changed slightly. The bonding strength between untreated coating, the coating heat treated at 600 ℃, the coating heat treated at 800 ℃ and the substrate zirconium alloy was 44.07, 44.12 and 44.08 MPa, respectively. After the heat treatment, various Cr-Al alloy phases including Al Cr2, Al8 Cr5, Al9 Cr17, Al9 Cr4, and Al86 Cr14 appear on the coatings, which contributed to reduction of the defects including surface pores and large particles. The bonding strength between the coatings and substrate changed slightly before and after heat treatment.
出处
《表面技术》
EI
CAS
CSCD
北大核心
2017年第12期78-83,共6页
Surface Technology
基金
国家科技重大专项子课题项目(2015ZX06004001-002)
湖南省重点学科建设项目([2011]76)~~
关键词
多弧离子镀
磁控溅射
热处理
Cr/Al涂层
组织形貌
结合强度
multi-arc ion plating
magnetron sputtering
heat treatment
Cr/A1 coating
microstructure morphology
bondingstrength
