1. Understanding the mechanism for the mechanical property degradation of a lithium disilicate glass-ceramic by annealing.
- Author
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Li, D., Li, X.C., Zhang, Z.Z., Zhang, S.F., and He, L.
- Subjects
LITHIUM silicates ,GLASS-ceramics ,ANNEALING of metals ,RESIDUAL stresses ,STRAINS & stresses (Mechanics) - Abstract
Post-crystallization annealing above the T g was applied to a lithium disilicate glass-ceramic with microstructure consisting of glassy matrix and rod-like lithium disilicate crystals, effect of the annealing on the mechanical behavior was investigated. Flexural strength and VIF toughness of the glass-ceramic unexpectedly decreased after the annealing. The mechanical behavior variation was understood based on residual micro-stress analysis. Coefficient of thermal expansion for the glassy matrix presented a tendency to increase after the annealing, which would enlarge the thermal expansion mismatch between the glassy matrix and the lithium disilicate crystals. As a result, the residual micro-stresses in the glass-ceramic abnormally increased with increasing the annealing time. The mechanical property degradation was attributed to the annealing-induced increase of the residual micro-stresses. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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