Pyrochlore-fluorite dual-phase high-entropy ceramic foams with extremely low thermal conductivity from particle-stabilized suspension

2021 ◽  
Vol 194 ◽  
pp. 113714
Author(s):  
Xuanyu Meng ◽  
Jie Xu ◽  
Jiatong Zhu ◽  
Ping Zhang ◽  
Artur Rydosz ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Dual Phase ◽  
Ceramic Foams ◽  
Low Thermal Conductivity ◽  
High Entropy

Highly Porous Zirconia Ceramic Foams with Low Thermal Conductivity from Particle-Stabilized Foams

2016 ◽  
Vol 99 (11) ◽  
pp. 3512-3515 ◽  
Author(s):  
Wen-Long Huo ◽  
Xiao-Yan Zhang ◽  
Yu-Gu Chen ◽  
Yu-Ju Lu ◽  
Wen-Ting Liu ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Zirconia Ceramic ◽  
Ceramic Foams ◽  
Low Thermal Conductivity ◽  
Porous Zirconia ◽  
Highly Porous

A novel high-entropy monoboride (Mo0.2Ta0.2Ni0.2Cr0.2W0.2)B with superhardness and low thermal conductivity

2020 ◽  
Vol 46 (17) ◽  
pp. 26626-26631
Author(s):  
Pengbo Zhao ◽  
Jinpeng Zhu ◽  
Yilin Zhang ◽  
Gang Shao ◽  
Hailong Wang ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Low Thermal Conductivity ◽  
High Entropy

scholarly journals High-entropy (Nd0.2Sm0.2Eu0.2Y0.2Yb0.2)4Al2O9 with good high temperature stability, low thermal conductivity and anisotropic thermal expansivity

2020 ◽  
Author(s):  
Zifan Zhao ◽  
Huimin Xiang ◽  
Heng Chen ◽  
Fu-zhi Dai ◽  
Xiaohui Wang ◽  
...  
Keyword(s):  
Phase Transition ◽  
Thermal Conductivity ◽  
Thermal Expansion ◽  
Rare Earth ◽  
High Temperature ◽  
Phase Stability ◽  
Temperature Phase ◽  
Low Thermal Conductivity ◽  
High Entropy ◽  
Anisotropic Thermal Expansion

Abstract The critical requirements for the environmental barrier coating (EBC) materials of silicon-based ceramic matrix composites (CMCs) including good tolerance to harsh environments, thermal expansion match with the interlayer mullite, good high-temperature phase stability and low thermal conductivity. Cuspidine-structured rare-earth aluminates RE4Al2O9 have been considered as candidates of EBCs for their superior mechanical and thermal properties, but the phase transition at high temperatures is a notable drawback of these materials. To suppress the phase transition and improve the phase stability, a novel cuspidine-structured rare-earth aluminate solid solution (Nd0.2Sm0.2Eu0.2Y0.2Yb0.2)4Al2O9 was designed and successfully synthesized inspired by entropy stabilization effect of high entropy ceramics. The as-synthesized (Nd0.2Sm0.2Eu0.2Y0.2Yb0.2)4Al2O9 exhibits close thermal expansion coefficient (6.96×10-6 /K at 300-1473 K) to that of mullite, good phase stability from 300 K to 1473 K, and low thermal conductivity (1.50 W·m-1·K-1 at room temperature). In addition, strong anisotropic thermal expansion has been observed compared to Y4Al2O9 and Yb4Al2O9. The mechanism for low thermal conductivity is attributed to the lattice distortion and mass difference of the constituent atoms while the anisotropic thermal expansion is due to the anisotropic chemical bonding enhanced by the large size rare earth cations.

Sign in / Sign up

Export Citation Format

Share Document