Thermal behaviour of sulphate-bearing multicomponent silicate–phosphate glasses

Abstract The present study provides a deep insight into the implications of sulphate addition on glass forming properties materials from SiO 2 –P O 5 –K O–MgO/CaO/MgOCaO systems, by combining: preliminary investigation as-synthesized (XRD, XRF, SEM–EDS), detailed characteristics their thermal behaviour (DSC), estimation various glass-stability parameters, in-depth analysis course crystallization and an identification crystallized products Raman imaging technique). Performed investigations revealed that obtaining amorphous is only possible in system containing MgO as alkaline earth modifier, whereas melts other tested compositions display high tendency to crystallize during cooling. Thermal showed influence SO 3 studied strongly depends composition, but generally such additive increased values transformation temperature decreased vitreous state range onset process, compared base samples, which signal decrease stability. Examination devitrificates character distribution domains structure materials. It was irrespective composition glass, it K 4 precipitates once capacity exceeded exists groupings either distributed voids silicate phase, or surrounding remnants gas bubbles embodied within body. results demonstrated provide guiding suggestions for development -containing silicate–phosphate glasses intended especially applications where release bioactive ions sought.