Size methods slip casting

Common consolidation methods include variations on pressing powders, plastic forming, slip casting and tape casting. The choice of which method to use for a given application is very dependent upon the shape, size and required dimensional tolerances of the final product, available capital outlay and desired productivity. Each of these methods is examined in turn below, followed by sintering, which turns the consolidated powders into a monolithic body with mechanical integrity. 

Companies that use bench plaster mould casting have two main requirements as regards the slurries cost control and consistency (of particle size, surface area, casting rate, viscosity and gel structure formation). Slurry producers have tried to address these needs in several ways. Improved statistical methods of analysis have been designed to respond to consistency concerns and increased-solid slurries have been developed to address both consistency and total cost requirements. In some cases, the slurry producer may recommend a traditional approach to slip adjustment (see sidebar Improving Casting Performance). New chenucal systems have also been proposed to improve slurry consistency. 

There are several factors in slip casting method. The porosity of the plaster mould is controlled by water content. The particle size of the powder should be relatively coarse to permit high level of vehicle permeability through the cast wall. Slip casting is widely used commercially because it enables the casting of complex shapes from an almost unlimited variety of ceramic composition, at a low cost. The most disadvantage of this process are low production rates and relatively short life of mould. 

By this method, the grain size, particle shape, agglomerate size, and specific surface area can be modified within a certain degree by controlling the precipitation and calcination conditions. Furthermore, its purity is also more easily controlled. For the applications of zirconiain the slip casting, tape casting, mold injection, particle size, specific surface, etc. are important characteristics. Well-controlled precipitated zirconia powder can be fairly uniform and fine. 

The grain size distribution for instance affects the adsorption capacity of clay, the viscosity of a casting slip, the plasticity of the raw material mixture and the reaction speed of the sintering process. Some methods to determine the grain size distribution are the simple sieving analysis which was elaborately discussed in chapter 9 and the more sophisticated methods ... 

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