ESTIMATION OF STANDARD-SIZE STRENGTH IN S ILICON-CARBIDE CERAMICS USING MINIATURE SPECIMENS

The effect of specimen size on the flexural strength of silicon carbid e ceramics was studied using miniature-size specimens. Fracture surfac e of these specimens was observed by SEM to determine the fracture ori gin. The strength of the miniature specimens increased with decreasing the specimen size, most of the fracture origins of the miniature spec imens being located on the specimen tensile surface. The strength of a standard-size silicon carbide specimen could be estimated from the st rength of the miniature specimens by invoking Weibull-size scaling wit h the effective surface area.