摘要
利用超音速火焰(HVOF)喷涂工艺在316L不锈钢表面制备NiCr-Cr3C2涂层。采用XRD、SEM、EDS、维氏硬度计、洛氏硬度计、摩擦磨损试验机等系统考察了不同热处理温度对NiCr-Cr3C2涂层组织结构、显微硬度及其分布、断裂韧性、结合强度以及耐磨性能的影响。结果表明:热处理可提高涂层结合强度。200~400℃,随温度升高,涂层显微硬度及耐磨损性能提高,并在400℃出现峰值,这源于固溶在NiCr合金相中的Cr3C2析出,形成大量细小二次碳化物硬质相,产生沉淀强化作用;高于400℃,涂层硬度下降,断裂韧性提高;1000℃热处理后,涂层结合强度降低。磨损试验表明:随热处理温度升高,磨损机制逐渐由磨粒磨损、疲劳磨损向磨粒磨损、黏着磨损转变。
The NiCr-Cr3C2 coating was prepared on the surface of 316L stainless steel by supersonic flame(HVOF)spraying.The effects of different heat treatment temperatures on the microstructure,microhardness,fracture toughness,bonding strength and wear resistance of HVOF sprayed coatings were studied by using XRD,SEM,EDS,micro-hardness measurement,Rockwell indentation test and wear testing machine,etc.The results show that,heat treatment can improve the bonding strength of the coating.The microhardness and wear resistance of the coating increase with the increase of temperature in 200-400℃,and the peak value appears at 400℃.This is due to the precipitation of Cr3C2 solid soluted in the NiCr alloy phase,resulting in the formation of a large number of fine secondary carbide hard phases and prodction of in precipitation strengthening effect.The hardness of the coating decreases and the fracture toughness increases when the temperature is higher than 400℃.The bonding strength of the coating decreases after heat treatment at 1000℃.The wear test shows that,with the increase of heat treatment temperature,the wear mechanism changes gradually from abrasive wear,fatigue wear to abrasive wear and adhesion wear.
作者
司永礼
王幸福
韩福生
朱建军
李志忠
凤国保
SI Yongli;WANG Xingfu;HAN Fusheng;ZHU Jianjun;LI Zhizhong;FENG Guobao(Institute of Solid State Physics,Hefei institutes of Physical Science,Chinese Academy of Science,Hefei 230031,China;University of Science and Technology of China,Hefei 230031,China;Anhui Weilong Remanufacturing Technology Co.,Ltd.,Ma On Shan 243000,China)
出处
《热加工工艺》
北大核心
2020年第8期136-142,146,共8页
Hot Working Technology
基金
国家863计划项目(2015AA034405)。
