Sintering behavior and thermal conductivity of Y_(2)O_(3) fully stabilized HfO_(2) ceramics  

作　　者：Chun Li Jian He Yue Ma 

机构地区：[1]School of Materials Science and Engineering,Beihang University,Beijing 100191,China [2]School of Energy and Power Engineering,Beihang University,Beijing 100191,China [3]Key Laboratory of High-Temperature Structural Materials and Coatings Technology(Ministry of Industry and Information Technology),Beihang University,Beijing 100191,China

出　　处：《Rare Metals》2021年第5期1255-1266,共12页稀有金属（英文版）

基　　金：financially sponsored by the National Natural Science Foundation of China(Nos.U1537212 and 51471019);China Postdoctoral Science Foundation(Nos.2017T100023 and 2016M600028);the National Key Research and Development Program of China(No.2016YFB0300901)。

摘　　要：A series of Y_(2)O_(3) fully stabilized HfO2 ceramics(Hf_(1-x)Y_(x)O_(2-0.5x),x=0.20,0.24,0.28,0.32,0.36 and 0.40)were synthesized by solid-state reaction at 1500℃.The phase composition,thermal conductivity and sintering behavior at 1400℃ of the ceramic bulks were studied.The Hf_(1-x)Y_(x)O_(2-0.5x) ceramics were comprised of pure cubic phase with disordered fluorite structure.No phase transformation occurred in the ceramics with Y3+doping concentration ranging from 0.24 to 0.36.Both Hf_(0.64)Y_(0.36)O_(1.82) and Hf_(0.6)Y_(0.4)O_(1.8) samples revealed the lowest grain growth rate when sintered at 1400℃,indicating good resistance to sintering.However,the Vicker’s hardness and Young’s modulus after annealed for 96 h at 1400℃ for the Hf_(0.64)Y_(0.36)O_(1.82) sample were 8.97 and 200 GPa,respectively,much lower than those of the Hf_(0.6)Y_(0.4)O_(1.8)(14.51 and 237 GPa,respectively).The thermal conductivity of Hf_(1-x)Y_(x)O_(2-0.5x) first decreased and then increased slowly as the Y3+content increased,and the associated mechanism was discussed.

关 键 词：Yttria fully stabilized hafnia SINTERING Mechanical properties Thermal conductivity 

分 类 号：TG174.4[金属学及工艺—金属表面处理] TK471[金属学及工艺—金属学]