TAPE CASTING OF LANTHANUM CHROMITE

The effects of process additives, ball milling, and solids loading wer e evaluated for tape casting suspensions of glycine-nitrate-synthesize d La0.7Ca0.31CrO3 powder, An optimized formulation was obtained based on rheological characterization, electrokinetic sonic amplitude measur ements, qualitative examination of green tapes, and the sintered micro structure, The tape casting formulation incorporated 66:34 methyl ethy l ketone/ethyl alcohol solvent, an aliphatic phosphate ester dispersan t, and 80 wt% (35 vol%) solids, The best binder/plasticizer system was 12 wt% (15 vol%) poly(isobutyl methacrylate) and 5 wt% (6.3 vol%) ben zyl butyl phthalate plasticizer (binder:plasticizer = 2.3), Cast tapes were sintered at 1300 degrees C for 2 h, producing a bulk density of 96.2% theoretical, with linear shrinkage of 22% and an approximate gra in size of 1.3 mu m.