David Christopher Forrest

US Patent:

7163138, Jan 16, 2007

Filed:

May 9, 2005

Appl. No.:

11/126510

Inventors:

Philip John Dudt - Rockville MD, US
David R. Forrest - Gaithersburg MD, US
Jennifer P. Nguyen - Sterling VA, US

Assignee:

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

International Classification:

B23K 20/12
B23K 31/02

US Classification:

2281121

Abstract:

An axially elongated cylindrical tool has a protrusion at a lower end thereof which is inserted into a metallic work piece substrate under pressure during rotation of the tool and displacement thereof in one direction. Mixing of a matrix of metal and particles by the protrusion occurs within a stir zone underlying the substrate surface which is thereby treated by dispersion of the particles therein in response to rotation of the tool. Influx of the hard particles into the work piece substrate is effected during said mixing by the rotating tool.

US Patent:

8114474, Feb 14, 2012

Filed:

Jun 21, 2011

Appl. No.:

13/164804

Inventors:

Philip J. Dudt - Rockville MD, US
David R. Forrest - Washington DC, US
Jennifer N. Wolk - Alexandria VA, US
Stephen Szpara - Hagerstown VA, US

Assignee:

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

International Classification:

B05D 1/02
B05D 3/12

US Classification:

427201, 427191, 427192, 427193, 427369

Abstract:

A metallic glass particle layer is applied to aluminum alloy armor and friction stir mixed into the surface in order to embed the material into the armor and to take advantage of its exceptional hardness. An advantage of the invention is that the hard material is an integral part of the armor, included within the body of the armor plate and not merely a surface coating. The advantage of the friction stir process is that it generates relatively low levels of heat and magnetic measurements show that the amorphous phase condition of the metallic glass is not deteriorated. The armor may be tempered to improve properties.