Tensile Response of Ceramics at the Microscale

The tensile strength of ceramic materials are well known to be highly size dependent, arising from the sampling of intrinsic flaws. As such, determining the true tensile strength of ceramics remains a challenge. Here, we investigate the distribution of tensile properties in armor ceramics (SiC, B4C, and SiC-B4C composite) at the microscale. By employing high throughput femtosecond laser based machining, tensile bars with critical dimensions less than 100 μm are fabricated. The specimens are tested in a custom micromechanical testing apparatus in order to create a statistically significant failure distribution. The fracture surfaces are further characterized to assess the failure mechanisms. Together these observations provide a clear picture of the intrinsic tensile response of armor ceramics.