Pages 291-292
To determine the fatigue fracture mechanisms of notched specimens of porous silicon carbide with a porosity of 37% and a mean pore size of 10μm, cyclic fatigue tests were carried out using four-point bendeing loading at room temperature. The crack length was determined from the compliance change under the assumption that the compliance change is caused solely by crack growth. The fatigue life increased with decreasing nominal stress level. The crack propagation rate first decreased with crack extention, and then turned to increase at crack length above about 0.7mm. SEM observations indicated that a fatigue crack grew in the bonding layer between particles.
