Densification procedure of Method and the porous preform to produce a densified porous billet

摘要

PURPOSE: To develop a densification process for a porous preliminarily formed article which does not exhibit inconsistency of the properties of different kinds of material. ;CONSTITUTION: When the porous preliminarily formed article made of a first material (example: carbon) is immersed in a liq. first reagent which contains a second material precursor (example: carbon precursor) and the preliminarily formed article is heated, the first reagent is decomposed to stick a second material (example: carbon) layer 41 to the surface of a basic material. A second reagent, which contains a third material precursor (example: ceramic precursor), is added to the first reagent so as to increase the ratio thereof to stick compsn. (example: carbon-ceramic) layers 43, 45 with a density gradient to the inside of the preliminarily formed article and, finally, to stick a third material (example: ceramic) layer 47 with the aid of the second reagent only. Densification, carbon oxydation preventing action and improvement in the thermally shock resistance are achieved by filling pores with a matrix material in the density gradients shown in a graph 51 or a graph 53. A mixture of ceramic, too, is acceptable as the matrix material.;COPYRIGHT: (C)1993,JPO