Science of Sintering 2003 Volume 35, Issue 1, Pages: 5-12
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Prediction of initial shape of functionally graded ceramic pre-forms for near-net-shape sintering
Maximenko A.L., Biest Der Van O., Olevsky E.A.
Sintering of macroscopically inhomogeneous ceramic components is always accompanied by shape distortions due to the difference in shrinkage rates of powder elements. The objective of the present investigation is the theoretical determination of initially distorted shapes of the green bodies needed to provide near-net-shape sintered components. Calculations are based on a finite element implementation of the continuum theory of sintering. In this theory, sintering is considered as a creep under the influence of the compressive “sintering stress”. To predict the initial shapes of the components the “inverse” numerical procedure is used when the component is assumed to swell from the final shape to the initial one under the influence of the pressure equal (with the exception of sign) to the sintering stress.
Keywords: functionally graded material, shape distortion, continuum theory of sintering