Modeling Tape Cast Ceramics With Multiple Layers of Fugitive Phase Materials

The fabrication of complex ceramic components requires new processing methods that are able to produce components with intricate geometries and accurate dimensions. The accuracy of the finished ceramic component depends upon precise control of the green ceramic body dimensions and uniformity prior to sintering. The authors are investigating the application of the fugitive phase approach, where a sacrificial material is used to form cavities or channels in the finished ceramic component. This paper, a continuation of a previous work, examines the lamination step of the fugitive phase approach for ceramic fabrication. The lamination step is where the fugitive phase pieces are combined with the tape cast green ceramic pieces. The multilayer green body is pressed to laminate the ceramic tape and fugitive phase layers together. Topological complexity is greatly increased when the tape cast ceramic pieces are interspersed with fugitive phase pieces to build up a consolidated multilayer green body. This paper examines the movement of the fugitive phase pieces, viscoelastic deformation of the ceramic phase, the filling of voids, pressure gradients, and the rebounding that occurs when the green ceramic body is removed from the press. This information will be used to complement parallel experimental investigations of the fugitive phase approach to ceramic fabrication.