Apparatus and a method for plating an Nd—Fe—B magnet

An apparatus for plating an Nd—Fe—B magnet using a target source material, said apparatus comprising:

• a furnace defining a vacuum chamber;
• an anode being elongated disposed in said vacuum chamber of said furnace;
• a cathode being elongated and disposed in said vacuum chamber of said furnace spaced from said anode and configured with the Nd—Fe—B magnet;
• at least one target source holder being elongated and disposed in said vacuum chamber and supporting said anode and said cathode, said anode and said cathode and said at least one target source being disposed in a parallel and spaced relationship with one another, the cathode configured for receiving the target source material to coat the Nd—Fe—B magnet, wherein said target source material contains metal and is selected from at least one of Dysprosium, Terbium, Holmium, Praseodymium, Neodymium, Niobium, Molybdenum, Copper, Titanium, Aluminum, and Cobalt;
• a thermal insulator disposed in said vacuum chamber surrounding said cathode and said at least one target source wherein said anode is located outside of said thermal insulator;
• a pulse bias power supply electrically connected to said cathode and said anode for cleaning and vaporizing the target source material to plate the target source material onto the Nd—Fe—B magnet;
• a DC bias power supply electrically connected to said at least one target source holder and said anode with said anode being grounded;
• said furnace defining an outlet aperture in fluid communication with said vacuum chamber for withdrawing air from said vacuum chamber to reduce pressure in said vacuum pressure and an inlet aperture in fluid communication with said vacuum chamber for feeding an inert gas to said vacuum chamber;
• said furnace defining an observation window for allowing a user to look into the vacuum chamber;
• and
• an optical pyrometer disposed adjacent to said observation window and facing toward said observation window and said vacuum chamber for monitoring a temperature in said vacuum chamber;
• said cathode and said at least one target source holder defining a predetermined distance between 5 mm and 200 mm between said cathode and said target source holder to increase efficiency of depositing the target source material on the Nd—Fe—B magnet and provide a uniform coating on the Nd—Fe—B magnet.