A study on devitrification and nucleation of calcium phosphate glass with Si3N4 additive

The devitrification phenomenon and nucleation of CaO/P2O5 glass with Si3N4 additive was investigated using thermal analysis techniques. To determine whether the devitrification begins at the surface or in the bulk of these glasses, we compared the exothermic peak temperature of DTA curves for coarse and fine particles, and it was found that the devitrification mechanism of CaO/P2O5 glass would change by adding Si3N4 powder. The addition of Si3N4 additive will induce the calcium phosphate glass to surface nucleation mechanism in this work, and the temperature of exothermic peak of DTA curves for calcium phosphate glass were also shift to higher temperature by increasing the weight percentage of Si3N4. On the other hand, the nucleation rate of calcium phosphate was decreased with increasing the weight percentage of Si3N4.