Journal of the European Ceramic Society ( IF 5.8 ) Pub Date : 2021-07-12 , DOI: 10.1016/j.jeurceramsoc.2021.07.012 Pavel Istomin 1 , Elena Istomina 1 , Aleksandr Nadutkin 1 , Vladislav Grass 1 , Anton Lysenkov 2 , Andrey Kudryavtsev 3
Fully dense high-entropy carbide (HEC) ceramic has been prepared from a mixture of the group IV and V transition metal oxides by a two-step technique, which involved the vacuum carbosilicothermic reduction (VCSTR) synthesis of a composite powder containing 75 vol.% HEC, 20 vol.% (Nb1-xMex)Si2 (where Me = Ti, Zr, Hf, Ta), and 5 vol.% SiC followed by hot pressing of the as-synthesized product. It was found that the reaction between (Nb1-xMex)Si2 and HEC took place during hot pressing, thereby allowing effective sintering to occur. The mechanical properties of the obtained nearly single-phase HEC ceramic were comparable to or even slightly better than those of HEC ceramics prepared by other methods. The use of VCSTR synthesis as a key step in the preparation of fully dense HEC ceramic was concluded to be effective both in lowering the sintering temperature and in improving the mechanical properties.
中文翻译:
氧化物碳硅热还原制备(Ti,Zr,Hf,Nb,Ta)C高熵碳化物陶瓷
已经通过两步技术从 IV 族和 V 族过渡金属氧化物的混合物制备了完全致密的高熵碳化物 (HEC) 陶瓷,其中涉及真空碳硅热还原 (VCSTR) 合成含有 75 vol. % HEC、20 vol.% (Nb 1-x Me x )Si 2(其中 Me = Ti、Zr、Hf、Ta)和 5 vol.% SiC,然后对合成产物进行热压。发现 (Nb 1-x Me x )Si 2和 HEC 发生在热压期间,从而允许发生有效的烧结。获得的近单相HEC陶瓷的力学性能与其他方法制备的HEC陶瓷相当甚至略好。使用 VCSTR 合成作为制备全致密 HEC 陶瓷的关键步骤被认为在降低烧结温度和改善机械性能方面都是有效的。