Investigating the deformation of lithium aluminosilicate glass ceramics in gradient stress field

Abstract Understanding the deformation behaviors of glass ceramics in the gradient stress field is crucial to improve their high precision processing in IC manufacturing industry. In this study, the quasistatic and time‐dependent mechanical responses of lithium aluminosilicate glass ceramics containing crystalline grains were evaluated by the instrumented indentation technique at two levels of loads: 3 mN and 2 N. Anomalous behaviors like enhanced creep rate and elastic softening were observed in coarse‐grained glass ceramics at 3 mN. They were rationalized as results of the spatial coupling effect between sampling volume and size of crystalline grains, as debonding and cracking may occur along the crystalline/glass interfaces in the coarse‐grained glass ceramics during shallow indentations. Relevant findings can improve the processing of the fine surface of glass ceramics in the advanced industry.