(Cr0.2Mn0.2Fe0.2Co0.2Mo0.2)B:A novel high-entropy monoboride with good electromagnetic interference shielding performance in K-band

• 作者: Haiming Zhang Biao Zhao Fu-Zhi Dai Huimin Xiang Zhili Zhang Yanchun Zhou
• 来源期刊: 材料科学技术（英文版）
• 年，卷（期）: 2021,（18）
• 页码范围: 58-65
• 页数: 8页
• 语种: 英文

摘要

A novel equimolar high-entropy(HE)transition metal monoboride,(Cr0.2Mn0.2Fe0.2Co0.2Mo0.2)B,was designed and prepared in powder and bulk form by high temperature elemental reac-tion method and spark plasma sintering(SPS)method,respectively.XRD analysis shows that HE(Cr0.2Mn0.2Fe0.2Co0.2Mo0.2)B possesses orthorhombic structure with Pnma space group.Through Rietveld refinement,the lattice parameters of HE(Cr0.2Mn0.2Fe0.2Co0.2Mo0.2)B are a=5.6675,b=2.9714,c=4.2209 and the theoretical density is 6.95 g/cm3.The Vickers hardness and electrical conductivity of HE(Cr0.2Mn0.2Fe0.2Co0.2Mo0.2)B bulk with relative density of 90％is 12.3±0.5 GPa and 0.49±0.04×106 S/m,respectively.Due to high electrical conductivity,HE(Cr0.2Mn0.2Fe0.2Co0.2Mo0.2)B bulk with 3.0 mm thickness displays superior EMI shielding performance in 18.0-26.5 GHz(K-band),and the average values of SET,SER,and SEA are 23.3 dB,13.9 dB,and 9.4 dB,respectively.The EMI shielding mechanism of HE(Cr0.2Mn0.2Fe0.2Co0.2Mo0.2)B mainly results from reflection.