Engineered Porosity via Tape Casting, Lamination and the Percolation of Pyrolyzable Particulates

Sintered ceramic preforms with open pore volumes from 20% to 80% (with no alteration in sintering shrinkage) were developed by adding pyrolyzable pore‐forming agents (PFAs) to a tape‐casting colloidal suspension. Sintered porous characteristics were directly controlled by the amount, size, and distribution of the PFA added to the green tape as well as adjustments made to the tape formulation. A conceptual model of the green tape microstructure was used to explain the influence of PFA and tape formulation on retained porosity and sintering shrinkage. The creation of a connected, open, porous network within the preform was the result of PFA particle percolation within the green body.