Sintering behavior and thermal conductivity of Y2O3 fully stabilized HfO2 ceramics

• 作者: Chun Li Jian He Yue Ma
• 来源期刊: 稀有金属（英文版）
• 年，卷（期）: 2021,（5）
• 所属期刊栏目: ORIGINAL ARTICLES
• 页码范围: 1255-1266
• 页数: 12页
• 语种: 英文

摘要

A series of Y2O3 fully stabilized HfO2 ceramics(Hf1-xYxO2-0.5x,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 Hf1-xYxO2-0.5x ceramics were comprised of pure cubic phase with disordered fluorite structure.No phase trans-formation occurred in the ceramics with Y3+doping con-centration ranging from 0.24 to 0.36.Both Hf0.64Y0.36O1.82 and Hf0.6Y0.4O1.8 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 Hf0.64Y0.36O1.82 sample were 8.97 and 200 GPa,respec-tively,much lower than those of the Hf0.6Y0.4O1.8(14.51 and 237 GPa,respectively).The thermal conductivity of Hf1-xYxO2-0.5x first decreased and then increased slowly as the Y3+content increased,and the associated mecha-nism was discussed.