Effects of Rare Earth CeO₂ on Microstructure and Properties of AlCoCuFeMnNi High-entropy Alloys

• Main Authors: PENG Zhu-qin, LI Jun-kui, LU Jin-bin, MA Ming-xing, WU Yu-ping
• Format: Article
• Language: zho
• Published: Journal of Materials Engineering 2018-08-01
• Series: Journal of Materials Engineering
• Subjects: high-entropy alloy; CeO₂; microstructure; wear property
• Online Access: http://jme.biam.ac.cn/CN/Y2018/V46/I8/91

The AlCoCuFeMnNi high-entropy alloy cladding layer with CeO₂ was prepared by plasma cladding technology on 45 steel. The microstructure and phase composition of the cladding layer were investigated by XRD, SEM and EDS, and its microhardness and wear property were also tested. The results show that the phase structure of the cladding layer is mainly composed of BCC dendrites and FCC interdendrites. Thermodynamic calculation shows a small amount of AlCoNi phase exists in the cladding layer without CeO₂, and a large number of Fe-rich precipitated particles in the dendrites is observed, the hardness value exhibits gradient changes from 260HV_0.2 to 420HV_0.2, and their friction coefficient is between 0.16 and 0.57. After adding 1%(mass fraction) CeO₂, the Fe diffusion decreases into cladding layer, and a 32<i>μ</i>m Fe-rich peritectic transition layer is formed on the bottom of the cladding layer. The average hardness value is about 400HV_0.2, and their friction coefficient is relatively stable (0.28-0.31). The mass loss of the layer with CeO₂ is 74.4% of that without CeO₂. The grain refinement strengthening is the main reason of the improvement of wear properties.