Low temperature spark plasma sintering of 45S5 Bioglass

Abstract 45S5 Bioglass® powder has been densified at low temperatures using Spark Plasma Sintering (SPS). By employing SPS with pressures ranging from 70 to 300 MPa, it was possible to achieve fully dense and completely amorphous 45S5 Bioglass® samples at temperatures as low as 500–550 °C. By increasing the sintering temperature up to 600 °C the dense samples crystallized to Na 2 CaSi 2 O 6 phase rather than Na 2 Ca 2 Si 3 O 9 which is usually achieved at higher temperature. Acellular in vitro test results in Simulated Body Fluid (SBF) revealed that SPSed samples sintered at 600 °C resulted in faster formation of hydroxyapatite compared to pressureless sintered ones (1050 °C), which were highly crystallized. Amorphous Bioglass® and/or Na 2 CaSi 2 O 6 phase prepared by SPS could potentially produce Bioglass® composites with increased bioactivity.