Structure, properties and in-vitro response of SiO2-Na2O-CaO-P2O5 system based glass-ceramics after partial replacement of Na2O by Li2O

Effect of lithium oxide substitution on the structure, in-vitro chemical dissolution and mechanical properties of melt derived 4555 based glass-ceramics in 46.1SiO(2) (24.4-x)Na2O 26.9CaO 2.6P(2)O(5) x Li2O (x = 0, 2, 4, 6, and 10 mole %) system was studied. Raman analysis had shown the presence of Q(2) silica tetrahedra and crystalline phosphorus in the glass-ceramics samples. Higher mechanical properties of lithia containing glass and glass-ceramics were noticed due to compact glass structure in presence of small sized Li+ ions. Hexagonal shaped combeite (Na2O center dot 2CaO center dot 3SiO(2)) was the only crystalline phase. Fourier transform infrared spectroscopy (FTIR) and Raman spectra confirmed formation of carbonated hydroxyapatite (HCA) on the glass-ceramics surface in SBF solution. Scanning electron microscopy (SEM) with energy dispersive X-ray analysis (EDX) corroborated cotton ball like morphology as carbonated hydroxyapatitel ayer on lithium containing glass-ceramics sample surface.

Automated summary

The study investigated the effect of lithium oxide substitution on the structure, chemical dissolution, and mechanical properties of melt derived 4555 based glass-ceramics. It was found that the presence of lithium led to the formation of carbonated hydroxyapatite on the surface of the glass-ceramics, and resulted in higher mechanical properties.