FORMATION OF COMPOSITE MATERIALS BY THE INWARD DIFFUSION AND PRECIPITATION OF THE MATRIX PHASE

Abstract

A process for preparing a composite of two or more continuous phases, one of which is tantalum carbide or a mixture of tantalum carbide and carbon which comprises (1) impregnating a preform of graphite or a similar material in the form of a porous block or woven fiber form with a reactive carbon source such as petroleum pitch, a coal tar pitch, a thermal setting resin, or a sugar; (2) pyrolyzing the reactive carbon source to form carbon; (3) impregnating the preform with either Ta(OCH3)5 or Ta(OCH2CH3)5 under anhydrous conditions; (4) hydrating the Ta(OCH3)5 or Ta(OCH2CH3)5 to precipitate Ta2O5 throughout the preform; and (5) heating the preform at a temperature of 1400 DEG C. or more until the Ta2O5 has reacted with the carbon to form tantalum carbide.

Source: Google Patents

35 USC §181 Secrecy Order

Inventor

• 1ROGER E. WILSON

Sensitive facility: Arlington VA (defense contractors)