| 摘要: |
| 用等离子熔覆技术在Q235钢上制备了CoCrFeMnNiCx（x=0, 0.05, 0.1, 0.2，x为摩尔分数）高熵合金熔覆层，并研究了熔覆层的合金成分，显微组织、相结构以及显微硬度。结果表明： C0、C0.05、C0.1和C0.2合金熔覆层的显微组织均为树枝晶结构，其中，C0合金熔覆层只形成了简单的面心立方相，其晶格常数为0.359 7 nm；加入C后，合金熔覆层仍以简单面心立方为主，只是晶格常数有所增加，分别为0.360 2（C0.05）、0.360 3（C0.1）和0.361 8（C0.2） nm；同时有少量Cr7C3生成，且随着C含量的增加，Cr7C3的形态由棒条状变为多边形颗粒状。由于少量的C元素在熔覆层中既可以作为固溶元素起到间隙固溶强化效果，也可与Cr元素形成Cr7C3起到第二相弥散强化作用，所以随含C量的增加，熔覆层显微硬度呈增大的趋势，当C的摩尔比为0.2时，熔覆层硬度达到354.7 HV0.5。 |
| 关键词: 等离子熔覆 高熵合金 显微组织 |
| DOI：10.3969/j.issn.1007-9289.2014.04.010 |
| 分类号: |
| 基金项目: |
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| Microstructure of CoCrFeMnNiCx High-entropy Alloy Prepared by Plasma Cladding |
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WANG Zhihui, QIN Xiaoting, HE Dingyong, CUI Li, JIANG Jianmin, ZHOU Zheng
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College of Materials Science and Engineering, Beijing University of Technology, Beijing 100124
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| Abstract: |
| The CoCrFeMnNiCx(x=0, 0.05, 0.1, 0.2, x is mole fraction) highentropy alloys cladding layers were prepared on the Q235 steel by plasma cladding. The component, microstructure, crystal structure and microhardness of the layers were investigated. The results show that the microstructure of the cladding layers consists of dendritic segregation. C0 alloy only contains single FCC phase, and the lattice constant is 0.359 7 nm. As carbon is added into the alloy, Cr7C3 appears and the lattice constants of FCC phase increase to 0.3602 (C0.05), 0.3603 (C0.1) and 0.3618 nm(C0.2), respectively. The morphologies of Cr7C3 change from stick to polygonal granular with increasing C. Element C in the cladding layer can not only be used as a solid solution element, but also form Cr7C3 with the element Cr to play dispersion strengthening effect. Therefore, the microhardness of the cladding layer increases with increasing C. The microhardness of the cladding layer reaches 354.7 HV0.05, when the mole ratio of C is 0.2. |
| Key words: plasma cladding highentropy alloy microstructure |
