Diffusion controlled oxygen transport and stability at the perovskite/electrolyte interface

New grades of sintered corundum armor (.alpha.-Al2O3) have been designed here to obtain a ballistic mass efficiency close to SiC and, preferentially, to exhibit a high optical in-line transmission by assocg. (i) a small sub-micron grain size with (ii) a very high d. and (iii) purity, and (iv) a microstructure that is free of flaws. Different ceramic technologies like dry (cold isostatic) pressing and casting approaches (with the option of free shaping) are investigated with respect to these objectives. Results of ballistic tests give evidence of a strong correlation of protective efficiency and rising hardness in fine-grained sintered Al2O3