Patent ID: 6589351
Filing Date: 2003-07-08
Classification: C23C

Abstract:
An electron beam physical vapor deposition coating apparatus comprising:a coating chamber containing a coating material, the coating chamber being operable at an elevated temperature and a subatmospheric pressure; an electron beam gun for projecting an electron beam into the coating chamber and onto the coating material, the electron beam gun being operable to melt and evaporate the coating material; a crucible through which the coating material is fed into the coating chamber, the crucible comprising a first member having a wall portion that surrounds and retains a molten pool of the coating material, a second portion defining an upper surface of the crucible, and a third portion surrounding and spaced apart from the wall portion so that the wall portion and the second and third portions define an enclosed annular-shaped cooling passage surrounding the wall portion, the crucible comprising a second member removably secured to the first member and having a wall portion surrounding an unmolten portion of the coating material, the second member defining an inlet to the passage and an outlet from the passage; and means for supporting an article in the coating chamber so that vapors of the coating material deposit on the article.