We propose a new design guideline for static fracture resistance of mechanically discontinuous ceramics. In this study, discontinuity ceramics using pottery materials were fabricated by intentionally introducing defects. Dense and porous layer laminates with very high interface consistency were used as a sample. The 3-point bending strength of the laminates was 40 % higher than that of the dense monolayer. This is thought to be that the excessive fracture energy was required to flatten the pores in the porous layer when a 3-point bending load was applied. Furthermore, the 3-point bending strength of laminates in which elastic modulus discontinuities were intentionally established by dividing the uniaxial pressing of dense pottery materials into several times was found to be 25 % higher than that of dense monolayer. Thus, in heterogeneous ceramics, high-strength materials could be created by intentionally introducing the gap in elastic modulus.

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