METAL PLASMA IMMERSION ION-IMPLANTATION AND DEPOSITION (MPIIID) - CHROMIUM ON MAGNESIUM

Chromium films have been deposited on magnesium by metal plasma immers ion ion implantation and deposition. With this method an intermixed la yer can be produced by ion implantation before film deposition. The mo st suitable process parameters for implantation have been determined. The plasma is produced by a cathodic are discharge operated in direct current mode and filtered by means of a curved magnetic filter. The ma ximum total ion current available at the filter exit is about 1.45% of the are current for chromium. This corresponds to a filter transmissi on of about 24%. The dependence of the particle content of the films o n the substrate position has been investigated. The corrosion behavior of the coated magnesium is improved greatly by reducing the particle content of the film as well as by the formation of an intermixed layer . (C) 1998 Elsevier Science S.A.