The Thermal Shock Behaviors of Y-TZP/Y-TZP-Al2O3 Composites having Dual Microstructure

이중조직을 갖는 Y-TZP/Y-TZP-$Al_2O_3$ 복합체의 열충격 거동

  • 황규홍 (경상대학교 무기재료공학과) ;
  • 김의훈 (삼화화성주식회사) ;
  • 김환 (서울대학교 무기재료공학과)
  • Published : 1992.04.01

Abstract

Duplex composites such as Y-TZP/Y-TZP-20 wt.% Al2O3 and Y-TZP/Y-TZP- 40 wt.% Al2O3 were made by mixing the sieve-shaked granules followed by isostatic pressing and sintering at 150$0^{\circ}C$ for 1 hour. So Y-TZP became matrix region and Y-TZP-20 wt.% Al2O3 or Y-TZP-40 wt.% Al2O3 became dispersed regions. In these composites, propagating cracks due to thermal shock always run into the dispersed region because these regions act as compressive zone due to low thermal expansion than matrix region. So duplexes having dispersed regions of Y-TZP-40 wt.% Al2O3 showed higher retained strength after thermal shock than matrix only composites because crack propagations were stopped more or less in the dispersed region. But when crack propagations were much more easy than matrix like Y-TZP-20 wt.% Al2O3 region, retained strength was decreased than the matrix only composites despite of the low initial strength.

Keywords

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