Weibull statistical analysis for vickers hardness of Al2O3/SiC composite according to the SiC concentration

Hardness is a characteristic value that indicates resistance to partial deformation or abrasion of the material surface. It is easy to measure, and data can quickly be obtained. It also shows correlation with mechanical properties, such as tensile strength. Al2O3/SiC composite with three concentrations of silicon carbide was sintered, and heat-treated at three different temperatures. The Vickers hardness of the as-received specimen and the heat-treatment specimen was analyzed by Weibull statistics, and its probability distribution characteristics were evaluated. Since an oxide layer was formed on the surface by the heat-treatment, the hardness of the specimen having high temperature heat-treatment was low. The shape parameter and the mean Vickers hardness decreased as the heat-treatment temperature increased, and the scale parameters showed smaller than those of the as-received specimen. The scale parameters of the 1,473 K specimen were larger than those of the as-received specimen, but those of the (1,573 and the 1,673) K specimens were smaller than those of the as-received specimen. The entire shape parameters, except for the 1,673 K specimen of AS15Y3, were smaller than those of the as-received specimen, and the dispersions were large.