Crystallized fraction and crystal size effects on the strength and toughness of lithium disilicate glass-ceramics

Author(s)

Senk, M. V. ; Mathias, I. ; Zanotto, E. D. ; Serbena, F. C.

• Document type: Journal article
• Source: Journal of the European Ceramic Society; v. 43, n. 8, p. 10-pg., 2023-03-13.

Abstract

This work investigated the variation in fracture strength and toughness of stoichiometric lithium disilicate (LS2) glass-ceramics as a function of crystal size (d) and crystallized volume fraction (f), with three average crystal sizes (8, 13 and 34 mu m) and a wide range of crystallized fractions (0-100 %). The fracture strength and toughness increased with increasing the crystallized volume fraction. For constant crystallized fraction, KIC increased with crystal size, indicating an R-curve behavior. The mean free path between the crystals limits the maximum size of the critical defect and is the crucial feature controlling fracture strength. Finally, we verified that the contribution to the toughness of R-curve mechanisms in this glass-ceramic is proportional to (f.d)1/2, which agrees with R-curve models for ceramics. (AU)

• FAPESP's process: 13/07793-6 - CEPIV - Center for Teaching, Research and Innovation in Glass
• Grantee: Edgar Dutra Zanotto
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC