Michael J Koczak

US Patent:

48349429, May 30, 1989

Filed:

Jan 29, 1988

Appl. No.:

7/150122

Inventors:

William E. Frazier - Philadelphia PA
Michael J. Koczak - Philadelphia PA

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

C22C 2100

US Classification:

420552

Abstract:

An aluminum-titanium alloy and a process of making it, the alloy consisting ssentially of aluminum, 4-6 wt. % titanium, 1-2 wt. % carbon, and 0. 1-0. 2 wt % oxygen. The alloy is an aluminum matrix supersaturated with titanium, and having throughout a fine, homogeneous dispersion of Al. sub. 3 Ti particles. It is fine grained and has grain boundary dispersoids of carbides and oxides, predominantly of aluminum. An aluminum-titanium melt is rapidly solidified and then mechanically alloyed in the presence of a carbon-bearing agent. The resulting powder is degassed and hot consolidated to form articles which exhibit high strength, ductility, and creep resistance at temperatures greater than 200. degree. C.

US Patent:

48083720, Feb 28, 1989

Filed:

Jan 23, 1986

Appl. No.:

6/821755

Inventors:

Michael J. Koczak - Philadelphia PA
K. Sharvan Kumar - Baltimore MD

Assignee:

Drexel University - Philadelphia PA

International Classification:

C22C 3200

US Classification:

420457

Abstract:

An in situ process is provided for producing a composite comprising a refractory material dispersed in a solid matrix. A molten composition comprising a matrix liquid, and at least one refractory carbide-forming component are provided, and a gas is introduced into the molten composition. A reactive component is also provided for reaction with the refractory material-forming component. The refractory material-forming component and reactive component react to form a refractory material dispersed in the matrix liquid, and the liquid composite is cooled to form a solid composite material. In one embodiment, the reactive component is a carbonaceous component in the form of a component of the gas, a solid in the gas or the molten composition, or both. The carbonaceous component is provided for reaction with a refractory carbide-forming component to yield a refractory carbide. In a preferred embodiment, the matrix liquid is molten aluminum and the refractory carbide-forming component is tantalum.