Study on thermophysical properties and phase evolution in Nd doped Li2O-Al2O3-SiO2 glass nucleated by multiple nucleating agents

­Effect of sintering treatment time on the sintering behaviour and thermal shock resistance of Li2O-Al2O3-SiO2 glass-ceramics

“…All A3 samples revealed a similar XRD diffractogram with both major and minor crystalline phases of β-spodumene (LiAlSi 2 O 6 ) and zirconium titanate (ZrTiO 4 ), respectively. A pronounced peak observed at 26° for all samples represented the presence of tetragonal β-spodumene [021] (ICDD: 00-035-0797), as similarly reported by other works [29][30][31][32], followed by other peaks at 19°, 23°, 28° and 49° (Figure 1). The nucleating agents of ZrO 2 and TiO 2 appeared as ZrTiO 4 [111] (ICDD: 00-035-0584) [19,33] peaked at 30° and 65°.…”

“…The decrease of A3_4 density might be due to the densification inhibition caused by the increased viscosity of glass network that can be also proven by the increase Si percentage in Figure 3. The density of all samples obtained in this study was within the range of LAS glass-ceramics density reported by other studies, 2.4-2.6 g/cm 3 [38,39], attributable to the presence of high-density spodumene as a major phase [32]. During the 1.5 h (A3_1) sintering treatment time, the LAS glass-ceramics was subjected to the first stage of sintering, where necks were formed between particles following the gradual grain growth leading to partial or incomplete densification.…”

Investigation of Isothermal Treatment on the Structural, Microstructure and Physical Properties of Li2O-Al2O3-SiO2 Glass-Ceramic

“…The density of sample A3 was also in the range of LAS glass-ceramic in a previous study [47]. The improvement in density is likely to be due to the presence of high-density spodumene as a major phase obtained in XRD [14]. On the other hand, apart from being a nucleating agent, TiO 2 also facilitates the densi cation of LAS glassceramic by increasing volume crystallisation, to yield crack-free denser LAS glass-ceramic [59].…”

“…Meanwhile, the coarser grain boundary deteriorates the mechanical properties of LAS glass-ceramic [14]. The grain size of sample A3 and A4 did not differ much but produced a signi cant effect on the density of the sample A3 as indicated in Table 4.…”

“…LAS glass-ceramic is often used in applications that require minimal thermal expansion at a higher temperature such as cooktop panels and high-temperature furnace windows [8][9][10]. The zero or negative CTE of LAS glass-ceramic is possessed by crystalline phases with highly anisotropic CTE, named βquartz [11,12], β-spodumene [13][14][15] and β-eucryptite [16,17]. β-spodumene is a solid solution derived from keatite with CTE ranging between 0.5-1.0 × 10 − 6 °C − 1 [18,19].…”