Polycrystalline ?-alumina due to numerous advantageslike sub-micron powders compared to other ceramic material, the ease ofcreating water suspension and excellent properties of sintering in the air isone of the most ceramic materials used in industry. On the other hand, Aluminaceramic grains sub-micron structure used for high mechanical load condition.Also traarent polycrystalline alumina samples have made with sub-microngrain to optimize the production process. Now the challenge of some advancedceramics is production process control parameters using nonosized ceramicpowders. So homogeneous piece with sub-micron grain and structure without faultat least cavities. Homogeneous density of particles in green body is essentialprecondition to provide full dense with superior properties of optic andmechanics. Perhaps the biggest improvement occurred in the last 20 years, theunderstanding of the impact of green body structure on sintering stage andbecause of this we have to use colloidal technique for compression of powders.Slip casting method modified used for this purpose. The initial body shaping tobe quite homogeneous and minimum density of the pores cannot guarantee completedensity alumina with minimum grain growth has very effective. The use ofdopants such as Mg, Y, La and Zr could be reduced grain growth, and alsoit cause to improves Real inline transmittances polycrystalline alumina invisible range is up to 50%. Use of advanced techniques such as Spark plasmasintering can cause density of the samples with at least amount of grain growthto reach higher than 98% relative density, which is not possible withconventional sintering without pressure.
