Sintering Of 3D-Printed Glass/Hap Composites

In this article the authors report the sintering of 3D-printed composites of 13-93 bioactive glass and hydroxyapatite (HAp) powders. The sintering process is characterized on conventionally produced powder compacts with varying HAp content. A numeric approximation of the densification kinetics is then obtained on the basis of Frenkel, MackenzieShuttleworth, and EinsteinRoscoe models, and optimized sintering conditions for 3D-printed structures are derived. Fully isotropic sintering of complex cellular composites is obtained by continuous heating to 750°C at a rate of 2 K/min for a HAp content of 40 wt%. The approach can readily be generalized for printing and sintering of similar glass-ceramic composites.