Development of a threshold strength in an aluminosilicate ceramic by annealing

Abstract

Annealing an aluminosilicate ceramic modified the strength distribution by creating a threshold strength level, which was readily observed on a Weibull plot. The threshold strength appeared to develop through surface-defect healing or modification and was maximized for annealing at 1,200{degree}C. It deteriorated for higher temperature annealing heat treatments, coincident with the extensive growth of large mullite crystals within the microstructure.