Patent ID: 6933460

Claim:
Treatment method for cleaning and/or heating a metal substrate ( 1 ), comprising feeding the substrate ( 1 ) along an axis of displacement ( 2 ) in a substantially continuous manner through a vacuum chamber ( 3 ), having a treatment zone in which an electric discharge ( 10 ), comprising a plasma, and a magnetic field are generated in a gas maintained at a pressure below atmospheric pressure, between at least the substrate ( 1 ), acting as an electrode, and at least one counter-electrode ( 9 ) to enable the substrate ( 1 ) to be bombarded by the ions produced in the electric discharge ( 10 ), generating a confining magnetic induction field entirely around the substrate ( 1 ) in the treatment zone so that the electric discharge ( 10 ) is confined to the area all around the substrate ( 1 ) in said treatment zone due to a confinement of electrons released in the electric discharge ( 10 ), whereby the confining magnetic induction field that is generated comprises a magnetic mirror through which the substrate ( 1 ) is fed.