The <i>In Situ</i> Preparation of MgAl₂O₄/YAG Eutectic Composites by Reaction Sintering Using Induction Heating

Abstract

High density MgAl2O4/YAG (yttrium aluminum garnet) eutectic composites were successfully prepared by in-situ reaction sintering using induction heating (IH). The effects of IH time and the starting materials composition on the phase composition and microstructure were investigated. The results showed that the eutectic composites consisted of only MgAl2O4 and YAG phase could be prepared by IH in a short time in a range of Al2O3/MgO ratio between 1~1.54. Compared to conventional sintering (CS), the solubility of Al2O3 in spinel is remarkably enhanced under the synergistic effects of high temperature and induced electromagnetic field. The higher YAG content facilitates the formation of more eutectic liquid phase, which favors to obtain a more homogeneous and denser interpenetrating network structure.