| 摘要 |
PURPOSE:To conduct local surface treatment, by introducing a gas contg. a material, which diffuses and permeates into the surface of a metal to be treated at high temp., into a vacuum vessel, and by arranging an auxiliary cathode facing to the surface portion of a metal as a cathode to be treated, apart from the cathode so as to increase the electrolytic dissociation density of the gas around the auxiliary electrode and to raise the treatment temp. CONSTITUTION:In a vacuum vessel 1, a cathode terminal 5 is connected to a material 2 to be treated, and an auxiliary electrode 20 for heating locally the portion 2a to be treated is arranged at a position 0.5-50mm, preferably 5-25mm apart from the surface of the portion 2a. After the vessel 1 is evacuated, H2 and CH4 etc. are introduced through a gas inlet 7, and a d.c. voltage is applied under vacuum across an anode terminal 4 and the cathode terminal 5 to produce glow discharge, hereby the portion 2a is heated to a temp. not lower than 400 deg.C, and the other portion to a temp. not higher than 350 deg.C. This method makes possible the local surface treatment of metallic material, in addn., at a small energy consumption for heating the metallic material. |
