碳黑含量对放电等离子烧结Fe-Cr-C/TiCN复合材料组织和耐磨性的影响  

Effect of Carbon Content on Microstructure and Wear Resistance of Fe-Cr-C/TiCN Composites by Spark Plasma Sintering

作　　者：李学军 刘颖[1] 叶金文[1] 周廷川 陈道颖 Li Xuejun;Liu Ying;Ye Jinwen;Zhou Tingchuan;Chen Daoying(College of Materials Science and Engineering,Sichuan University,Chengdu 610065,China)

机构地区：[1]四川大学材料科学与工程学院,四川成都610065

出　　处：《稀有金属材料与工程》2021年第7期2273-2280,共8页Rare Metal Materials and Engineering

基　　金：National Key Research and Development Plan of China (2017YFB0305900);Sichuan Science and Technology Program (2020ZDZX0008)。

摘　　要：采用机械合金化和放电等离子烧结法制备了不同碳含量的Fe-Cr-C/TiCN复合材料。通过扫描电镜、X射线衍射、维氏硬度和球-盘式摩擦试验,系统地研究了碳含量对Fe-Cr-C/TiCN复合材料组织和磨损性能的影响。结果表明,在含碳量为1.0%~5.0%(质量分数,下同)的烧结样品中形成了(Cr, Fe)7C3碳化物,而当碳含量达到4.0%~5.0%时,出现了(Cr, Fe)3C相。碳含量对Fe-Cr-C/TiCN复合材料的组织均匀性和致密化有着较为重要的影响,当烧结温度为~1000℃时,致密度由未加碳时的95.0%提高到的99.7%(含碳量为3.0%),说明已实现了完全致密化。当含碳量为3.0%时,维氏硬度达到11 940 MPa。此外,添加适量的碳(3.0%)有助于获得良好的磨损性能,即摩擦系数波动范围小,平均摩擦系数为0.320,磨损率为6.8×10^(-4) mm^(3)·N^(-1)·m^(-1)。Fe-Cr-C/TiCN composites with different carbon contents were prepared via mechanical alloying followed by spark plasma sintering. The effects of carbon black content on the microstructure and wear properties of Fe-Cr-C/TiCN composites were systematically investigated by scanning electron microscopy, X-ray diffraction, Vickers hardness test, and ball-on-disk type tribotest.The results show that the(Cr, Fe)7C3 carbides form in the sintered specimens with 1 wt%~5 wt% carbon, but(Cr, Fe)3C phases appear when the carbon black content reaches 4 wt%~5 wt%. Carbon black content plays a significant role in the microstructure uniformity and densification of the Fe-Cr-C/TiCN composites. When the sintering temperature is ~1000 ℃, the relative density of specimen without carbon addition increases from 95.0% to 99.7% of the specimen with carbon addition of 3 wt%, indicating that the full densification is realized. High Vickers hardness of 11 940 MPa is achieved for the specimen with carbon addition of 3 wt%.Furthermore, adding an appropriate amount of carbon(3 wt%) contributes to the excellent wear properties with narrow fluctuation ranges of friction coefficient, suggesting an average friction coefficient of 0.320 and wear rate of 6.8×10^(-4) mm^(3)·N^(-1)·m^(-1).

关 键 词：Fe-Cr-C/TiCN复合材料 碳 放电等离子烧结 显微组织和耐磨性 

分 类 号：TB333[一般工业技术—材料科学与工程]