Use in ceramic processing

However, the growing interest during the last ten years in the area of sol-gel processes has focussed primarily on silica glasses or ceramics made of materials such as Al, Zr, Ti whose many precursors form a versatile basis for sophisticated chemistry. Yet, there have been very few reports about the chemistry of solution precursors for elements such as Y (10X11), Bi (12) or Cu (13) and to our knowledge, before 1987, none about their use in ceramic processing. Therefore, the majority of the works that have been described to date in the... 

Chemical hazards. Some of the chemicals used in ceramic processing are toxic. One important example is lead and its oxides, which are widely used in the production of certain types of glasses and pigments. Care should be taken to read safety data sheets that accompany any chemicals and to take the necessary preventative action. Other safety issues can arise from unwanted reactions that occur within the furnace. 

Liquids are used in ceramic processing have two major functions (i) providing fluidity for the powder to be processed during the forming and (ii) dissolving the additives to be introduced into the powder as solvents, so as to disperse the additives throughout the powder uniformly. 

All surface analytical techniques (with the exception of Rutherford back-scattering) require the use of ultrahigh vacuum environment. The analysis conditions are therefore rather limited and do not correspond to those normally used in ceramic processing where the powder experiences fairly prolonged exposure to the atmosphere. Although the techniques described here derive their usefulness from being truly surface sensitive, they can also be used to provide information... 

Table 6.8 Common Plasticizers Used in Ceramic Processing...

Forming additives or processing aids (2,33—37) are commonly used to render ceramic powders more processible. Binders and plasticizers (qv) are typically added to improve or aid dry powder and plastic forming, whereas deflocculants, surfactants (qv), and antifoams are commonly used in slurry processing. 

Preceramic polymer precursors (45,68) can be used to make ceramic composites from polymer ceramic mixtures that transform to the desired material when heated. Preceramic polymers have been used to produce oxide ceramics and are of considerable interest in nonoxide ceramic powder processing. Low ceramic yields and incomplete burnout currently limit the use of preceramic polymers in ceramics processing. 

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