PURPOSE: To prevent the adhesion of a spraying powder to a negative electrode and the welding loss of the negative electrode without losing the axial feed of the spraying powder to a plasma jet and the stability of plasma.
CONSTITUTION: In a plasma spraying torch provided with a positive electrode having a plasma generating chamber 2 having a plasma jet nozzle 3 on the top end and an operating gas feed passage 5 having an insulator 4 bonded to its base part and continued to the plasma generating chamber 2; and a negative electrode 9 provided through the central part of the insulator 4, its top end being situated in the plasma generating chamber 2, and having an operating gas and flame coating powder feed passage 8 in the center part, the negative electrode 9 is formed of a copper negative electrode 9 having a cooling water passage 10 and HfC or ZrCl 12 on the top end, and a Tic coating film 13 is formed on the negative electrode inner surface in the plasma generating chamber 2.
JPH01191768 | BRAKE DISK MADE OF ALUMINUM ALLOY |
WO/2004/035856 | PROCESS FOR METAL-COATING WOOD |
NOTOMI HIROSHI