Effects of composition on crystallization behaviour and mechanical properties of bioactive glass-ceramics in the MgO–CaO–SiO2–P2O5 system

Abstract The effects of replacement of P 2 O 5 by SiO 2 , on the crystallization behaviour, mechanical properties and bioactivity of glass-ceramics in the MgO–CaO–SiO 2 –P 2 O 5 system were investigated. By decreasing P 2 O 5 and increasing SiO 2 , the apatite crystallization peaks disappeared from DTA traces, whereas the wollastonite peaks remained unchanged. XRD results showed that by decreasing P 2 O 5 and increasing SiO 2 contents, the amount of apatite and wollastonite phases were decreased and increased, respectively. The diametral compression strength (DSC) and indentation fracture toughness (IFT) values gradually raised with increasing wollastonite content. The best results obtained for the specimens with the maximum amount of wollastonite were 36.6 and 2.74 MPa m 1/2 for DCS and IFT, respectively. The bioactivity of specimens after being soaked in a simulated body fluid for one month were examined by SEM/EDX and FT–IR. A thin apatite layer was formed even on the surface of specimens containing the minimum amount of apatite phase.