In this study, the change of the height of the crystallization peak, (δT)p, and the reciprocal of the crystallization peak temperature, 1/Tp, were investigated as a function of nucleation heat‐treatment time for two silicate glasses: (2BaO·TiO2·2SiO2—B2TS2) and lithium disilicate (Li2O·2SiO2—LS2). Then, monolithic pieces were heat‐treated in a differential scanning calorimetry furnace. The results demonstrated that these glasses behave similarly with respect to peak crystallization temperature, i.e., 1/Tp decreases with the heating rate for nucleation (φn). However, the results with B2TS2 samples demonstrated that (δT)p increases with rising heating rates for nucleation (shorter nucleation heat treatment times), φn, whereas (δT)p was found to decrease with φn in the LS2 specimens. This unexpected behavior is attributed to the extensive overlapping of the I(T) and U(T) curves shown by fresnoite glass.

In this study, lithium disilicate (LS2) glass samples with different particle sizes ranging from less than 105 to 850 μm were prepared. These specimens were inserted in a Pt‐Rh DSC crucible and heated to 850°C at different rates (ϕ = 0.5–30 K/min) to identify their crystallization peaks. The activation energies for the overall crystallization (E) and the Avrami coefficient (n) were evaluated using different nonisothermal models. Specifically, n was evaluated using the Augis–Benett model and the Ozawa method, and E was evaluated using the Kissinger and Ligero methods. As expected, the coarse particles mainly crystallized in the volume, while surface crystallization was predominant in the samples with particle sizes of less than 350 μm. This result was confirmed through SEM analysis of the double stage heat‐treated samples. In contrast with previous studies, our results demonstrated that the activation energy decreased as the particle size increased. In addition, no clear correlation between the peak intensity (δTp) and the particle size was observed.

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