The Role of Rheological Parameters on Drying Behaviour of a Water-Based Cast Tape

Abstract In this paper we studied the migration of secondary particles in tape casting of a non-Newtonian ceramic slurry through a generalised local viscosity function in order to obtain the particle distribution along tape thickness. The particle distribution were then used to calculate porosity and permeability of the tapes. We, moreover, linked the aforementioned results to a coupled free-flow-porous-media model on the Representative Elementary Volume (REV) scale for simulating room-temperature drying of the tapes with flow of a relatively dry air (relative humidity of 25%). Finally, we investigated the influence of rheological parameters, i.e. the power-law index, η, and the consistency factor, m, of a typical Ostwald-de Waele power-law fluid on the resultant drying behaviour of the tapes. The results showed that the low consistency and low power-law index values reduce the drying rate (slightly) as well as the final drying time, that favours the manufacturing of tapes by reducing the risk of crack initiation/growth in ceramics.