Elastoplastic coupling to model cold ceramic powder compaction

TL;DR

This paper presents an elastoplastic coupling model for simulating cold ceramic powder compaction, enabling prediction of density, residual stress, and elastic properties during forming processes.

Contribution

The authors extend a previous constitutive model to simulate large strain powder compaction, incorporating friction effects and residual stress prediction in finite element analysis.

Findings

Finite element simulations match experimental density and stress distributions.

The model accurately predicts residual stresses and elastic properties in green bodies.

Friction effects are effectively incorporated into the compaction simulation.

Abstract

The simulation of industrial processes involving cold compaction of powders allows for the optimization of the production of both traditional and advanced ceramics. The capabilities of a constitutive model previously proposed by the authors are explored to simulate simple forming processes, both in the small and in the large strain formulation. The model is based on the concept of elastoplastic coupling providing a relation between density changes and variation of elastic properties and has been tailored to describe the transition between a granular ceramic powder and a dense green body. Finite element simulations have been compared with experiments on an alumina ready-to-press powder and an aluminum silicate spray-dried granulate. The simulations show that it is possible to take into account friction at the die wall and to predict the state of residual stress, density distribution and elastic properties in the green body at the end of the forming process.