Airco, Inc.

Jersey Nuclear-avco Isotopes, Inc.

Kurt D Kennedy

Glen R Scheuermann

E Darrell Erikson

Apparatus for reducing convection current heat loss in an electron beam evaporator. A material to be evaporated (evaporant) is placed in the crucible of an electron beam evaporation source along with a porous mass formed of a powdered or finely divided solid to act as an impedance to convection currents. A feed system is employed to replenish the supply of evaporant as it is vaporized.

Mixed phase evaporation source

An improved method is disclosed for coating substrates, such as turbine engine parts, at high rates by a physical vapor deposition process. The substrate to be coated and a vapor source, such as a metal alloy, heated by an electron beam, are placed in a chamber in which a gas pressure of greater than about 5 mT is maintained. When the source material is evaporated at a very high rate, such as greater than about 0.1 g/s or 13 g/s.m.sup. 2, the vapor is collimated and the collimation increases as the gas pressure or the evaporation rate increases. Collimation of the vapor allows a much higher deposition rate for a given evaporation power. Further, a much higher fraction of the evaporated material is deposited on the substrate. Despite the collimation, evaporated material deposits on areas of the substrate which are not in line-of-sight of the vapor source. If desired a substrate bias can be applied to bombard the substrate with ions before and during coating.

Growing community of inventors

Berkeley, CA, United States of America

Kurt D Kennedy