The camber of asymmetric laminates has been experimentally measured and predicted. Two cases are distinguished: (i) sintering of a viscous layer on a viscous substrate and (ii) sintering of a viscous layer on an elastic substrate. In the first case, particular attention is paid to the microstructure of the shrinking layer: a gradient in porosity as well as in pore size has been found along the thickness. Microstructural observations have been rationalized through an asymmetric stress state in the shrinking layer. In the second case, substrate cracking is predicted as function of Young's modulus and thickness ratio of the elastic substrate.V. Jayaram-contributing editor

The sintering behavior of a glass–ceramic (commercial material Ceramtape GC) was characterized using the discontinuous sinter‐forging technique. The uniaxial viscosity Ep and the viscous Poisson's ratio np of the composite body were determined as a function of density. Particular attention was paid to microstructural changes in order to quantify the anisotropy induced by load application. Pores and alumina particles were found to be both oriented perpendicular to the applied load direction. Finally, the experimental results were used to predict the value of the hydrostatic sintering stress.

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The sintering behavior of symmetric laminates has been experimentally measured and modeled. Two cases are distinguished: (i) sintering of a viscous layer between viscous substrates and (ii) sintering of a viscous layer between elastic substrates. A simple model based on a persisting isotropic microstructure allowed computation of developing in‐plane stresses. These in conjunction with a viscous Poisson's coefficient were taken to predict out‐of‐plane stresses and finally densification rate. This approach, however, proved unsuccessful to predict the large observed differences in densification rate between laminates constrained by either green or dense alumina substrates. The discrepancy was found to be due to widely different microstructures developing with different degrees of elastic constraint. Pore area and pore and particle orientation were determined to quantify these microstructural changes.

The sintering behavior of the commercial material Ceramtape GC, a glass‐ceramic composite, is characterized with the help of the continuum mechanical description. The sinter‐forging technique permits to determine the uniaxial viscosity of the porous ceramic body as a function of density. At an isothermal temperature of 840°C, the uniaxial viscosity varies from 0.2 to 6 GPa.s with increasing relative density from 76% to 97%. Continuous and discontinuous sinter‐forging allows the characterization of the effect induced by the load.