Estimate microstructure development from sintering shrinkage: A kinetic field approach

Abstract

Methods such as the master sintering curve (MSC) or the kinetics method proposed by Wang and Raj (WR) are well-known techniques for determining the activation energy of sintering. However, a comprehensive sintering model also requires knowledge of porosity-dependent moduli, various constants, and grain growth behaviour. In this work, we detail a new method that allows the step-by-step identification of all the required sintering parameters. It is based on an experimental design that employs the MSC method and does not require additional tests. This work aims to estimate the grain growth behaviour during sintering from the shrinkage observed during the final stage, avoiding the use of a time-consuming interrupted-sintering study and subsequent analysis by microscopy. The grain growth behaviour was estimated by determining the densification behaviour and temperature-dependent parameters at the intermediate stage of sintering followed by determination of grain growth behaviour during the final stage based on the observed reduction in the rate of densification. The experimental MSC was incorporated into a Skorohod–Olevsky-based model, allowing the sintering behaviour to be predicted with high accuracy. This method is superior to the traditional MSC approach as it allows the sintering trajectory to be modelled and incorporates parameters that are compatible with finite element simulation.