摘要
利用激光熔覆技术在0Cr18Ni9不锈钢基体上制备NiCr/Cr3C2耐磨涂层与NiCr/Cr3C2-30%WS2耐磨自润滑涂层,采用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、能谱仪(EDS)分析了涂层的物相组成及显微组织。在室温、300℃和600℃下分别测试了上述涂层的干滑动摩擦学性能,并讨论其磨损机理。实验结果表明:添加WS2的熔覆涂层主要有Cr7C3、(Cr,W)C碳化物增强相、γ-(Fe,Ni)/Cr7C3共晶增韧相、WS2及CrS润滑相。两种涂层都随温度的升高,摩擦因数降低,而磨损率增大。在室温及300℃时,添加WS2涂层由于润滑相的作用拥有较好的减摩耐磨性能。在600℃时,由于涂层中碳化物硬质相的强度降低,两种涂层的磨损率显著增大。
The self-lubricating wear-resistant NiCr/Cr3C2-30% WS2 coating and wear-resistant NiCr/ Cr3C2 coating were fabricated by laser cladding on 0Crl8Ni9 austenitic stainless steel. The phase com- positions and microstructures were investigated by X-ray diffractometer (XRD), scanning electron mi- croscope (SEM) and energy dispersive spectrometer (EDS). The tribological properties of the fabrica ted composite coatings were evaluated under dry sliding condition at room-temperature (RT), 300℃ and 600℃, respectively, and the wear mechanisms were discussed. The results show that the phase constituents of coating added with WS2 are composed of Cr7C3, (Cr, W)C reinforcement carbides, ductile phase of 7-(Fe, Ni)/CrTC3 eutectic, and WS2, CrS lubricants. The friction coefficients of a bove two coatings both decrease with the rising of temperature, but the wear rates both increase. At room-temperature and 300~C, the coating added with WS2 has superior friction-reducing and wear-re- sistance properties as a result of the presence of WS2 and CrS lubricants. However, the wear rates of two coatings significantly increase due to the hardness reducing of carbides at 600~C.
出处
《材料工程》
EI
CAS
CSCD
北大核心
2013年第11期26-31,37,共7页
Journal of Materials Engineering
基金
江苏省自然科学基金(BK20131155)
苏州市科技计划项目(SYG201233
SG201273
SYG201203)
江苏省高校自然科学基金(11KJB460008)
国家自然科学基金(51205266
61078019)
关键词
激光熔覆
高温耐磨复合涂层
固体润滑
laser cladding
high-temperature wear-resistant composite coating
solid lubrication