Tube chemical gas deposition method of preparing titanium nitride coated titanium carbide for titanium carbide/silicon nitride composites

Abstract

A tube chemical vapor deposition method of preparing titanium carbide/silicon nitride (TiC/Si.sub.3 N.sub.4) composites. To prepare such composites, titanium carbide (TiC) is first coated with a homogeneous layer of titanium nitride (Ti.sub.3 N.sub.4). A gas mixture of titanium chloride (TiCl.sub.4), nitrogen (N.sub.2), hydrogen (H.sub.2) with an appropriate ratio is introduced into a reaction chamber where the tube chemical vapor deposition takes place. The temperature of the reaction for the sintering process is between 900.degree. C. to 1200.degree. C., under a total pressure of 1 atm. While maintaining a constant temperature for 1 to 2 hours, deposition of titanium nitride (Ti.sub.3 N.sub.4) onto titanium carbide (TiC) powder takes place. The adoption of the simple tube chemical vapor deposition technique for the present invention not only enables a mass production of homogeneously coated titanium carbide (TiC) particulates, but also further enhances the hardness and toughness as well as other mechanical properties of silicon based composites, such as a titanium carbide/silicon nitride (TiC/Si.sub.3 N.sub.4) composite.

Dependencies are inferred from the claim text.