Pressureless spark plasma-sintered Bioglass (R) 45S5 with enhanced mechanical properties and stress-induced new phase formation

摘要

Commercial Bioglass (R) 45S5 powder was sintered using spark plasma sintering (SPS) technique without the assistance of mechanical pressure with heating and cooling rate of 100 degrees C/min, dwell temperature of 1050 degrees C and dwell time of 30 min. Such route enabled the production of samples exhibiting superior mechanical properties in comparison with Bioglass (R) sintered in furnace. In particular, flexural strength and fracture toughness reached values close to those of apatite-wollastonite bioceramics, already widely used in clinical applications. The residual stresses implemented by indentation promoted the formation of a new phase in samples sintered by SPS. Complementary use of Raman and energy dispersive spectroscopy (EDS) indicated the phase as sodium carbide and a formation mechanism was proposed. (C) 2017 Elsevier Ltd. All rights reserved.