Preparation of WC/CoCrFeNiAl0.2 high-entropy-alloy composites by high-gravity combustion synthesis  

作　　者：Guan-nan Zhang Xiao Yang Zeng-chao Yang Yong Li Gang He Jiang-tao Li 

机构地区：[1]Key Laboratory of Cryogenics,Technical Institute of Physics and Chemistry,Chinese Academy of Sciences,Beijing 100190,China [2]Center of Materials Science and Optoelectronics Engineering,University of Chinese Academy of Sciences,Beijing 100049,China

出　　处：《International Journal of Minerals,Metallurgy and Materials》2020年第2期244-251,共8页矿物冶金与材料学报（英文版）

基　　金：financially supported by the National Key R&D Program of China (No. 2017YFB0310303);the National Natural Science Foundation of China (No. 51702332);the Key Laboratory of Cryogenics, TIPC, CAS (Nos. CRYOQN201705 and CRYOQN201507)

摘　　要：The WC/CoCrFeNiAl0.2 high-entropy alloy(HEA)composites were prepared through high-gravity combustion synthesis.The preparation method is presented below.First,using a designed suitable multiphase thermite system,the molten CoCrFeNiAl0.2 HEA was fabricated using low-cost metal oxides.The molten HEA was subsequently infiltrated into the WC layer to fabricate WC/CoCrFeNiAl0.2 composites in a highgravity field.The porosity of the WC/CoCrFeNiAl0.2 composites was down-regulated,and their compressive yield strength was up-regulated when the high-gravity field was increased from 600g to 1500g because this infiltration process of a HEA melt into the WC layer is driven by centrifugal force.The WC particles in the composites exhibited a gradient distribution along the direction of the centrifugal force,which was attributed to the combined action of the high-gravity field and the temperature gradient field.The Vickers hardness of the sample was down-regulated from 9.53 to 7.41 GPa along the direction of the centrifugal force.The WC/CoCrFeNiAl0.2 high-entropy alloy（HEA） composites were prepared through high-gravity combustion synthesis. The preparation method is presented below. First, using a designed suitable multiphase thermite system, the molten CoCrFeNiAl0.2 HEA was fabricated using low-cost metal oxides. The molten HEA was subsequently infiltrated into the WC layer to fabricate WC/CoCrFeNiAl0.2 composites in a highgravity field. The porosity of the WC/CoCrFeNiAl0.2 composites was down-regulated, and their compressive yield strength was up-regulated when the high-gravity field was increased from 600 g to 1500 g because this infiltration process of a HEA melt into the WC layer is driven by centrifugal force. The WC particles in the composites exhibited a gradient distribution along the direction of the centrifugal force, which was attributed to the combined action of the high-gravity field and the temperature gradient field. The Vickers hardness of the sample was down-regulated from9.53 to 7.41 GPa along the direction of the centrifugal force.

关 键 词：COMPOSITES high-entropy alloy high-gravity combustion synthesis gradient material 

分 类 号：TB33[一般工业技术—材料科学与工程]