| 摘要 |
PURPOSE:To form a uniform ion-nitrided layer on the whole surface of a metal to be treated, by use of a pulse discharge voltage from several tens of Hz to several MHz in ion-nitriding of the metal surface by glow discharge. CONSTITUTION:Metal parts 6 are placed on a supporting stand 7 contained in an airtight vessel 1. The vessel 1 is evacuated and a treating gas is introduced therein. A pulse voltage ranging from several tens of Hz to several MHz is applied to the suporting stand 7 as a cathode and to the vessel 1 as an anode to produce glow discharge in order to ion-nitride the surfaces of the metal parts 6 by sputtering with gas ions. The corner C or the bottom D of a U-shaped groove is difficult to be ion-nitrided. So that a pulse signals are given from a pulse generator 14 through an on-off time setting circuit 15 to an invetor 13 to apply a pulse voltage of a large frequency in order to produce glow discharge along the parts to be treated. Hereby the above described C, D are coated with ion-nitrided layer of sufficient thickness. |
