摘要
为了提高低温离子渗硫层的厚度、均匀性和基体的硬度,采用激光熔覆、超声滚压和离子渗硫技术在45钢表面制备复合改性层。采用SEM-EDS、XRD和硬度计等手段对比分析了激光熔覆层纳米化前后渗硫层的组织形貌、成分分布及相组成;利用UMT-3摩擦磨损试验机分别考察了不同渗硫试样及其对摩偶件在干摩擦条件下的摩擦学性能。结果表明:无论熔覆层是否纳米化,其渗硫层均由FeS、FeS2、WS2、NiS2、CrS2、FeNi3和Cr-Ni-Fe-C物相组成,与未纳米化渗硫层相比,纳米化渗硫层厚度提高了2倍,厚度更为均匀,硫化物含量、Fe S相所占比例和基体的硬度提高,摩擦系数下降了0.16,耐磨性提高了0.44倍,对摩件的耐磨性提高了1.66倍。这归因于激光熔覆纳米晶层具有较高的硬度和化学活性。
In order to improve the thickness and uniformity of low temperature ion sulfurizing layer and the hardness of substrate,laser cladding,ultrasonic rolling and ion sulfurizing technology were used to prepare composite modified layer on 45 steel surfaces.The microstructure,composition distribution and phase composition of the sulfurized layer before and after nanocrystallization of the laser cladding layer were analyzed and compared by means of SEM-EDS,XRD and hardness tester.Moreover,the tribological properties of different sulphurized specimens and their friction couples under dry friction conditions were investigated by using UMT-3 friction testing machine.Results showed that no matter whether the cladding coatings were nano-treated,the nano-sulphurized layer was composed of FeS,FeS2,WS2,NiS2,CrS2,Fe Ni3and Cr-Ni-Fe-C phases.Compared with the un-nano-sulfurized layer,and the thickness of the nano-sulfurized layer was increased by 2 times,and the thickness presented more uniform.The proportion of sulfide content and Fe S phase increased,and the hardness of the substrate increased.Furthermore,the friction coefficient decreased by 0.16,and the wear resistance increased by 0.44 times,as well as the wear resistance of the friction parts increased by 1.66 times.All these characteristics attributed to the high hardness and chemical activity of the nanocrystalline surface layer.
作者
王海港
王守忠
WANG Hai-gang;WANG Shou-zhong(Department of Automotive and Construction Engineering,Shangqiu Polytechnic,Shangqiu 476005,China;Department of Biological Engineering,Shangqiu Polytechnic,Shangqiu 476005,China)
出处
《材料保护》
CAS
CSCD
北大核心
2020年第7期67-73,84,共8页
Materials Protection
基金
河南省重点研发与推广专项
新能源汽车创新人才培养研究基金项目(182400410408)资助。
关键词
激光熔覆
表面纳米化
离子渗硫
组织性能
摩擦磨损
laser cladding
surface nanocrystallization
ion sulfurizing
microstructure
tribological properties
