Novel high-entropy ultra-high temperature ceramics with enhanced ablation resistance  

作　　者：Pan Zhang Xiong-Jun Liu Guang-Yu He Fu-Kuo Chiang Hui Wang Yuan Wu Sui-He Jiang Xiao-Bin Zhang Zhao-Ping Lu 

机构地区：[1]Beijing Advanced Innovation Center for Materials Genome Engineering,State Key Laboratory for Advanced Metals and Materials,University of Science and Technology Beijing,Beijing,100083,China [2]Institute for Materials Intelligent Technology,Liaoning Academy of Materials,Shenyang,110004,China [3]Science and Technology on Plasma Dynamics Laboratory,Air Force Engineering University,Xi’an,710038,China [4]National Institute of Clean-and-Low-Carbon Energy,Beijing,102211,China

出　　处：《Rare Metals》2024年第12期6559-6570,共12页稀有金属(英文版)

基　　金：financially supported by the National Natural Science Foundation of China (Nos.52271003,52071024,52271003 and 52101188);the Funds for Creative Research Groups of China (No.51921001);the Projects of International Cooperation and Exchanges of NSFC (Nos.51961160729 and 52061135207);111 Project (No.BP0719004);the Program for Changjiang Scholars and Innovative Research Team in University of China (No.IRT_14R05);the Fundamental Research Fund for the Central Universities of China;the Project of Science and Technology on Plasma Dynamics Laboratory,Air Force Engineering University,Xi'an,China (No.126142202210206);the State Key Lab for Advanced Metals and Materials (No.2022-Z10)。

摘　　要：Ultra-high temperature ceramics(UHTCs) offer great potential for applications in extreme service environments,such as hypersonic vehicles,rockets and re-entry spacecraft.However,the severe ablation caused by highspeed heat flow scouring and high-temperature oxidation limits the engineering application of UHTCs.In this work,we report a novel high-entropy UHTC(Ti_(0.2)Zr_(0.2)V_(0.2)Nb_(0.2)Cr_(0.2))(C_(0.5)N_(0.5)),which exhibits superior ablation resistance and light weight compared with traditional UHTCs.Specifically,at a temperature of 2650 K,the mass ablation rate of the material was measured as1.025×10^(-2)g·s^(-1),and the density was calculated to be 6.7 g·cm^(-3).The impressive ablation resistance of(Ti_(0.2)Zr_(0.2)V_(0.2)Nb_(0.2)Cr_(0.2))(C_(0.5)N_(0.5)) is attributed to the incorporation of a self-healing mechanism,which is associated with the in-situ formation of a medium-entropy oxide(TiVCr)O_(2) during the ablation process.The mediumentropy oxide can seal pores and cracks to retard oxygen diffusion and prevent the material from fragmentation,thereby resulting in outstanding ablation resistance.

关 键 词：High-entropy ceramics Ultra-high temperature ceramics Ablation mechanism 

分 类 号：TQ174.1[化学工程—陶瓷工业]