The ceramic industry depends on the use and control of a wide variety of clay and mineral suspensions in water for most forming processes. The consistency, stability and predictability of these aqueous suspensions are crucial to the successful manufacture of ceramic articles and minimising losses.
Currently the industry uses simple measurements of density and fluidity to determine the suspension properties and the addition of deflocculants, flocculants etc. to control their behaviour in production. The problem is that even though these suspension properties can be measured accurately and controlled within specified limits, many suspensions still exhibit anomalous behaviour during the making process leading to unacceptable production losses. There is an urgent need, therefore, for a method of characterising these suspensions such that their performance in the various forming processes can be assured.
To gather sufficient background information relating to zeta potential (a measure of the stability of a suspension) and ceramic suspensions to:
* Improve the efficiency of ceramic suspension and so production control;
* Improve the control of glaze materials so ensuring consistent high quality glaze applications;
* Allow the forming characteristics of clay suspensions to be predicted and controlled.
This will allow the following industrial objectives to be met;
* Improve the efficiency and productivity of ceramic manufacture;
* Reduce the rework of suspensions which are within specification but unsuitable for use;
* Reduce wastage of toxic ceramic materials.
Start meeting held 12th March 1998 confirmed objectives and work programme. Selection, preparation and supply of base materials commenced.
Ceramic raw materials used in body slips and glaze suspensions will be investigated by traditional methods and correlated with zeta potential and rheological analysis in order to provide information to allow the behaviour of a suspension to be predicted through attention to its composition.
This will be achieved by looking at individual materials and their characteristics to gain an understanding of their effect on zeta potential and hence rheology and stability of suspension. The effect of additives on suspension properties will also be assessed. Once the materials have been characterised the effect of zeta potential on body characteristics and forming processes will be determined as will the effect on the glaze application properties.
Funding SchemeCRS - Cooperative research contracts
ST4 7LQ Stoke-on-trent
531 19 Lidkoping
ST4 7AF Stoke-on-trent
65599 Dornburg - Langendernbach