| 摘要 |
PURPOSE:To make it possible to reform the surface layer of a light alloy where the setting of conditions has been difficult in the surface treatment in which the additive of ceramic powder or the different kind of metal powder is mixed into the molten part by removing an oxide film at the treated part with the reversed-polarity current of an AC plasma arc. CONSTITUTION:A work W consisting of a light alloy such as an Al alloy is positioned on a holder, a plasma torch 2 is approached to the work, and an arc is generated between an electrode 8 and the part of the work W to be treated in the atmosphere replaced by the plasma gas. The part is cleaned by a reversed-polarity current, and the penetration is increased by the straight- polarity current. Consequently, the oxide film on the surface of the work W is cleaned off, and the concentrated melting of the internal base material is smoothly performed. A ceramic powder 18 is simultaneously discharged from a powdery material transport pipe 14. |
