Method of coating the interior surface of hollow objects with a diffusion coating

US6866886B2 · kind B2 · utility

Assignee

• Battelle Memorial Institute · CH

Inventors

• Shawn D. Knowles · St. Francis, US
• David J. Senor · West Richland, US
• Steven V. Forbes · Burbank, US
• Roger N. Johnson · Hagaman, US
• Glenn W. Hollenberg · Dayton, US

Key dates

• Filing date: Apr 2, 2003
• Grant date: Mar 15, 2005
• Expiry date: Sep 23, 2023

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S118/13
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

A method for forming a diffusion coating on the interior of surface of a hollow object wherein a filament, extending through a hollow object and adjacent to the interior surface of the object, is provided, with a coating material, in a vacuum. An electrical current is then applied to the filament to resistively heat the filament to a temperature sufficient to transfer the coating material from the filament to the interior surface of the object. The filament is electrically isolated from the object while the filament is being resistively heated. Preferably, the filament is provided as a tungsten filament or molybdenum filament. Preferably, the coating materials are selected from the group consisting of Ag, Al, As, Au, Ba, Be, Bi, Ca, Cd, Co, Cr, Cu, Dy, Er, Eu, Fe, Ga, Ge, Hg, In, K, Li, Mg, Mn, Na, Ni P, Pb, Pd, Pr, S, Sb, Sc, Se, Si, Sn, Sr, Te, Tl, Y, Yb, Zn, and combinations thereof. The invention additionally allows for the formation of nitrides, hydrides, or carbides of all the possible coating materials, where such compounds exist, by providing a partial pressure of nitrogen, hydrogen, hydrocarbons, or combination thereof, within the vacuum.