Study of the Non-Isothermal Crystallization Kinetics of Lithium Disilicate Glass Ceramic

摘要: The glass ceramic with the crystals of lithium disilicate Li2O · 2SiO2 (LS2) as main crystal phase is one prospective materials in field restorative dentistry. In this study, crystallization kinetics LS2 obtained from base system SiO2–Li2O–Al2O3–K2O–P2O5 were investigated by non-isothermal method using differential thermal analysis at four different heating rates. DTA curves showed exothermic peaks over temperature ranges 645–683 and 807–845°C. metasilicate, SiO2 (LS), disilicate, crystallized these respective ranges, was established XRD technique. kinetic parameters calculated Kissinger plot Augis-Bennett equations for analysis. activation energy growth, EC1= 236 kJ/mol, EC2 = 340 Avrami parameters, n1 1.46–1.67, n2 2.73–2.91, together results SEM observations, indicated that mechanism LS substantial surface while dominant bulk crystallization. transition also determined EV = 516 kJ/mol.