Fracture Behavior of <TEX>$Al_2O_3$</TEX> Macro-composites with Layered and Fibrous Structure

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J. Korean Ceram. Soc. > Volume 34(7); 1997 > Article

Journal of the Korean Ceramic Society 1997;34(7): 758.

층상 및 섬유상 $Al_2O_3$ 거시복합체의 파괴거동

신동우, 윤대현, 박삼식, 김해두¹

경상대학교 재료공학부 무기복합재료연구실, 첨단소재연구소
¹한국기계연구원 재료기술연구부 요업재료그룹

Fracture Behavior of $Al_2O_3$ Macro-composites with Layered and Fibrous Structure

ABSTRACT

Non-brittle fracture behaviour of the two composite structures made of two different brittle materials was investigated using 3-point bending test. First, the layered and fibrous macro-composites were fabricated using the material easily formed, yet showing a brittle fracture behaviour similar to ceramics. The layered and fibrous Al2O3 /Al2O3 composites with weak interface were also fabricated using plate of 2 mm thickness and rod of 3 mm diameter respectively. Comparison of the mechanical properties between these two structures was performed in the lights of flexural strength and work of fracture for the composites consisting of Al2O3 and simulated materials respectively. The strength ratio of layered structure to the monolith of same volume was 0.6 and the ratio of fibrous one was about 0.2 for the composites made of simulated brittle material. The ratio of the work of fracture of the fibrous to the layered was 0.47. For Al2O3/Al2O3 composites, the strength ratio of layered and fibrous structures to the monolith with same volume were about 0.6 and 0.2 respectively. The ratio of work of fracture of the fibrous to the layered was 0.6. These confirmed that the layered structure was superior to the fibrous one in terms of flexural strength and work of fracture.

Key words: Non-brittle ceramic structure, Layered structure, Fibrous structure, $Al_2O_3/Al_2O_3$ composites