Dynamic and Quasi-Static Fracture Toughness of $Al_2O_3$ and $Al_2O_3$ Ceramic Matrix Composite Reinforced with Sic Whiskers

$Al_2O_3$$Al_2O_3$ -$SiC_w$ 복합재료의 동적 및 정적 파괴인성에 관한 연구

  • 조경목 (포항공과대학 공과대학 금속공학과) ;
  • 이성학 (포항공과대학 재료·금속공학과) ;
  • 표성규 (포항공과대학 재료·금속공학과) ;
  • 장영원 (포항공과대학 재료·금속공학과)
  • Published : 1990.04.01

Abstract

This paper presents the influence of the loading rate on the room temperature fracture toughness of a brittle Al2O3 and a SiC whisker reinforced Al2O3 composite. Dynamic fracture toughness tests were conduced using compressive fatigue pre-cracked notched round bars loaded in tension to produce a stress intensity rate K1=106 MPa√m/sec. The experimental results show that for each loading rate the fracture toughness values obtained for the ceramic matrix composite are higher than the corresponding values for the single phase alumina. In addition, both the reinforced and unreinforced ceramic are singnificantly tougher under dynamic loading than static loading. This dynamic and quasi-static fracture initiation behaviro can be interpreted by identifying quantitatively the mode of fractuer initiation as a function of loading rate.

Keywords

References

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