Magnesite-chrome composites have been prepared by utilizing sintered magnesite and friable chrome ore in presence of titania as additive. Three types of batch compositions containing 5% Cr2O3, 18% Cr2O3 and 30% Cr2O3 have been selected for developing mag-chrome composites. The aggregates were developed by first vibro milling the raw materials and then additives were incorporated in wt.% along with 5% PVA solution as binder to the different batches. It was then properly mixed by fluidized bed mixer and after sieving in 20-mesh BS sieve briquettes were formed uniaxially at a pressure of 100 MPa. The briquettes were first air dried and subsequently oven dried at 110 +/- 5 degreesC for 24 It. Finally, the green briquettes were fired at 1700 and 1750 degreesC in electrically program controlled muffle furnace. The physical properties as well as thermo-mechanical properties and microstructural studies of the sintered aggregates have been evaluated. The common feature observed in the microstructures is the exsolution of spine] phase in magnesia grains. The hot properties of the composites are superior when the Cr2O3 content is increased to 30%. Additives played a significant role in improving the bulk density and strength. (C) 2003 Elsevier Ltd and Techna Group S.r.l. All rights reserved
