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This work aimed to explore the effect of high pressures at room temperature on the vibrational modes and the thermal properties and stability of barium disilicate glass (BaO‐2SiO2) (BS2). The BS2 was prepared through the conventional melting route at atmospheric pressure. After being submitted to different pressure values (2.5 GPa, 4.0 GPa, and 7.7 GPa) and room temperature, the samples were characterized ex situ by Raman spectroscopy and differential thermal analysis. With this, it is possible to see that the pressure modifies the Raman vibrational modes of the glass, in the region associated with the Si‐O‐Si symmetrical bending modes. The Si‐O symmetrical stretching vibrational modes (Qn) remain unchanged, however there are changes on values of glass transition and decrease crystallization temperature, as well as the parameters of thermal stability of the glass.

This work explored the permanent changes a high pressure (HP) processing could cause on nucleation, Raman vibrational modes, thermal, and mechanical properties of the Na 2 O • 2CaO • 3SiO 2 (N 1 C 2 S 3 ) glass. It was shown that, with higher pressure values, the number of nuclei per unit of volume, N V , has decreased. Raman spectra showed no significant changes in the vibrational modes; however, the differential thermal analysis performed indicated that the glass transition temperatures, T g , were higher than the pristine glass sample and that HP caused the glass to be less stable. The Vickers indentation radial cracks remained constant; however, the lateral cracks increased in size, indicating that the glass is more stressed after HP, and therefore, the relaxation time for nucleation will be higher, lowering N V further, as observed.