Shrinkage and dimensional accuracy of porous ceramics derived from capillary suspensions

Abstract

Shrinkage and dimensional accuracy are of particular importance for industrial material production. High dimensional accuracy directly lowers finishing works and cost. Capillary suspension processing is a novel, easy method to produce highly porous ceramic materials. Their shrinkage and shape accuracy is investigated during processing using a laser microscope. The total shrinkage is reduced by 20% for capillary suspension compared to pure suspension. This results from an increase in linear shape accuracy for top radii as well as height. The linear shape accuracy is increased by 6% in top radius and by 16% in height by using the capillary suspension phenomenon. We also show that this capillary suspension method is applicable for continuous shaping processes, like extrusion. The combination of an easy, robust processing route with known dimensional accuracy and applicability for continuous shaping processes makes this capillary suspension processing route highly desirable for industrial processes.