Superposed flow of CIM compounds

Abstract

Superposition of steady shear and oscillatory flows represents the possibility to investigate viscoelastic behaviour of the materials which are processed under complex deformations far from simple steady or oscillatory shear flows. Ceramic-based compounds intended for Ceramic Injection Moulding (CIM) undergo deformation through channels under various conditions. Their parallel superposed steady and oscillatory shear flows were measured on a cone-plate rheometer. Flow properties at high shear rates were evaluated on a capillary rheometer. The compounds showed highly non-Newtonian behaviour and apparent yield stress; their viscoelastic properties were influenced remarkably under the superposed shear flow at low shear rate and angular frequency; and they exhibited significantly different behaviour than fibre-filled systems.