Finite Element Analysis of Sintering Process for Functionally Graded Materials.

Abstract

As a part of the computer aided design of functionally graded materials (FGM), a method of the sintering analysis is proposed to avoid sintering defects in graded powder compacts such as warpage, crack, separation and so on. The sintering behavior of the mixtures composed of a ceramic and a metal powder with various mixing ratios is investigated as a typical component of FGM. Variations in sintering rate due to composition of the different two powders are revealed and a constitutive model for sintering of mixed powder compacts is constructed with the effect of mixture and the interaction between the two powder regions taken into consideration. The constitutive model provides a good fit of the sintering shrinkage-time curves obtained by the experiment. The finite element analysis of the sintering process of graded powder compacts is conducted using the constitutive model. The stress generated in the powder compacts during sintering is computed to predict a fracture initiation site among the layers.