Patent ID: 8562901
Filing Date: 2013-10-22
Classification: B28B,C04B

Abstract:
1. A method for producing a porous continuous-fiber-reinforced ceramic matrix composite structure with no matrix shrinkage cracks comprising: a) infiltrating, ceramic fibers or fiber preforms with a slurry containing camphene, at least one ceramic powder matrix forming material having a bimodal size distribution, and a binder to form an infiltrated fiber or fiber preform; b) stacking the infiltrated fiber or fiber preform into a desired thickness and orientation to form a stacked infiltrated fiber or fiber preform; c) consolidating the stacked infiltrated fiber or fiber preform into a green composite at a first temperature of less than 100° C. and a pressure up to 300 psi, wherein the camphene occupies a plurality of pores in the green composite; d) freeze-drying the green composite and eliminating the camphene through sublimation in air or under vacuum to form a crack-free ceramic matrix surrounding a rigid fiber network, wherein the crack-free ceramic matrix surrounding the rigid fiber network preserves and defines the plurality of pores occupied by the camphene during the consolidation step; and e) sintering the green composite at a second temperature of greater than 1000° C. to obtain the porous continuous-fiber-reinforced ceramic matrix composite structure.