Hierarchical porous(Ta_(0.2)Nb_(0.2)Ti_(0.2)Zr_(0.2)Hf_(0.2))C high-entropy ceramics prepared by a self-foaming method for thermal insulation  

作　　者：Cuiyan Li Ruinan Gao Haibo Ouyang Tianzhan Shen Zihao Chen Yanlei Li 

机构地区：[1]Key Laboratory for Green Manufacturing&Functional Application of Inorganic Materials,School of Materials Science and Engineering,Shaanxi University of Science and Technology,Xi’an 710021,China

出　　处：《Journal of Advanced Ceramics》2024年第7期956-966,共11页先进陶瓷（英文）

基　　金：This research was supported by the National Natural Science Foundation of China(Nos.52173299 and 52372087);the Natural Science Foundation of Shaanxi Province(No.2021JZ-51).

摘　　要：To meet the emerging demands for thermal protection materials for hypersonic aircraft,developing porous ultrahigh-temperature ceramics with both robust mechanical properties and superior thermal insulation performance is a critical challenge.Herein,we report novel porous(Ta_(0.2)Nb_(0.2)Ti_(0.2)Zr_(0.2)Hf_(0.2))C high-entropy carbide(PHEC)ceramics fabricated by a self-foaming method using commercially available metal chloride and furfuryl alcohol(FA)as precursors.The PHEC ceramics are constructed of microspheres with a size of 2µm,leading to a high porosity of 91.3%and an interconnected frame.These microspheres consist of high-entropy carbide grains(20 nm),resulting in abundant interfaces and nanosized pores in the PHEC ceramics.Due to its unique hierarchical structure,the prepared PHEC ceramics have outstanding compressive strength(28.1±2 MPa)and exceptionally low thermal conductivity(κ_(T),0.046 W·m^(-1)·K^(-1))at room temperature.This makes it a promising thermal insulation materials for ultrahigh temperature applications.This work provides a cost-effective and facile strategy for producing porous ultrahigh-temperature ceramics.

关 键 词：porous ceramics high-entropy carbides hierarchical structure thermal insulation self-foaming 

分 类 号：TB33[一般工业技术—材料科学与工程]