Alkali‐free processing of advanced open‐celled sinter‐crystallized glass‐ceramics

The cooling of a melt corresponding to the eutectic between wollastonite (CaSiO3) and diopside (CaMgSi2O6) determines the synthesis of an interesting example of alkali-free bioactive glass, easily converted into glass-ceramics featuring two silicate phases, coupled also with åkermanite (Ca2MgSi2O7), by sinter-crystallization of fine glass powders at 1000°C. The fabrication of scaffolds by digital light processing of glass powders suspended in a photo-curable, sacrificial binder, is a well-established technique; the present paper aims at disclosing novel approaches, concerning the topology of scaffolds, offering components with remarkable strength, especially in bending conditions. As an alternative, glass-ceramic foams were fabricated by the firing of porous precursors derived from the gelation of suspensions of glass powders in alkali-free basic aqueous solution.