Effect of carbon content on microstructure, hardness and wear resistance of CoCrFeMnNiCx high-entropy alloys
Effect of carbon content on microstructure, hardness and wear resistance of CoCrFeMnNiCx high-entropy alloys
复制标题
碳含量对CoCrFeMnNiCx高熵合金显微组织、硬度和耐磨性的影响
DOI：
10.1016/j.jallcom.2020.156533
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发表时间：
2020
影响因子：
6.2
通讯作者：
Chao Zhang
中科院分区：
文献类型：
--
作者：
Jin-Kun Xiao;Hong Tan;Juan Chen;Ashlie Martini;Chao Zhang
采用机械合金化和放电等离子烧结技术制备了一组CoCrFeMnNiCx（x = 0，0.3，0.6，0.9，1.2）高熵合金（HEAs）。系统研究了碳含量对CoCrFeMnNiCxHEAs的显微组织、硬度、抗划伤性和耐磨性的影响。结果表明，CoCrFeMnNiCxHEAs具有FCC和M7 C3两相结构。随着碳含量的增加，M7 C3相含量和孔隙率增加。HEAs的硬度通过碳合金化显著提高，从CoCrFeMnNi的327.8 HV提高到CoCrFeMnNiC0.6的566.4 HV。M7 C3相含量和气孔率是影响硬度的两个相互竞争的因素。CoCrFeMnNiC0.6合金具有最高的抗划伤性和耐磨性。CoCrFeMnNiC0.6的磨损率（0.47 × 10− 5 mm 3/N·m）比CoCrFeMnNi的磨损率（6.5 × 10− 5 mm 3/N·m）低一个数量级以上，与匹配材料Si 3 N4的磨损率相同。这是由于硬质M7 C3碳化物的析出和低孔隙率造成的。抗划伤性和耐磨性与硬度呈正相关。CoCrFeMnNiCxHEAs的磨损主要由剥层磨损和磨粒磨损共同作用。
A set of CoCrFeMnNiCx(x = 0, 0.3, 0.6, 0.9, 1.2) high-entropy alloys (HEAs) were prepared using mechanical alloying and spark plasma sintering. The influence of carbon content on the microstructure, hardness, scratch resistance and wear resistance of the CoCrFeMnNiCxHEAs was systematically investigated. The results show that the CoCrFeMnNiCxHEAs have a dual-phase structure comprised of FCC and M7C3phases. The M7C3phase content and porosity are found to increase with increasing the carbon content. The hardness of the HEAs is significantly enhanced by carbon alloying from 327.8 HV for CoCrFeMnNi to 566.4 HV for CoCrFeMnNiC0.6. The M7C3phase content and porosity are two competing factors that affect the hardness. The CoCrFeMnNiC0.6exhibits the highest scratch and wear resistances of the prepared samples. The wear rate of CoCrFeMnNiC0.6(0.47 × 10−5mm3/N·m) is more than an order magnitude lower than that of the CoCrFeMnNi (6.5 × 10−5mm3/N·m) and is of the same magnitude with the mating material Si3N4. This is due to the precipitation of hard M7C3carbides and low porosity. The scratch and wear resistances are positively correlated with the hardness. Both delamination wear and abrasive wear contribute to the wear of CoCrFeMnNiCxHEAs.