Reactive infiltration of magnesium vapor into alumina powder compacts

The strengthening and densification of Al2O3 powder compacts were achieved by reacting powder compacts with Mg and N-2 vapors. The phases AlN, MgO, an d MgAl2O4 appeared in the reacted region of the compact according to the fo llowing equation, (1 + alpha)Al2O3(s) + 3Mg(g) + N-2(g) --> (3 - alpha) MgO (s) + alpha MgAl2O4(s) + 2AlN(s)(0 less than or equal to alpha less than or equal to 3). The weight of the compact increased with process time and tem perature because of the incorporation of the vapors. This reaction was acco mpanied by the expansion and densification of the compact. The size of the Al2O3 powder particles affected the densification behavior of the compact. (C) 1999 Elsevier Science Limited. All rights reserved.