Chrome-free Passivation of Mg-MAGPASS-COAT®

Basics

MAGPASS-COAT® is a process for the chrome-free passivation of magnesium-based materials. Coating with MAGPASS-COAT® is carried out, for instance, using immersion bath method. The workpiece is immersed in a chrome-free, inorganic and aquaeous passivation solution and it then develops a conversion layer on the workpiece surface. The conversion layer consists of oxides of the passivation solution and the base material. It is electrically conductive and it acts as an intermediate layer for following treatments like paintwork or gluing.
Chrome-free Passivation of Mg-MAGPASS-COAT®
Housing for spot welding guns; on the right once passivated with chromium-free MAGPASS-COAT® (Photo: C&C Bark GmbH).
 

Properties

A MAGPASS-COAT® layer with a thickness of less than 1 µm provides temporary corrosion resistance. It is electrically conductive and improves the adhesion of paints and gluing. It is especially well-suited for intermediate layers for post-treatments. A high-degree of corrosion resistance is reached with a subsequent treatment with sealing and/or powder coating. The layer's colour varies from grey to golden brown depending on the alloy of the treated material.
 

Materials

The MAGPASS-COAT® process is suitable for the coating of all magnesium-based materials and it is a high-grade equivalent for standard chromating.
 

Applications

The MAGPASS-COAT® process can be used in a targeted way as an equivalent of existing chromating processes: the plating produces uniform layers true to original contours and it ensures the coating of even the most complex surface shapes such as, for instance, edges, cavities, reliefs, boreholes, blind holes or undercuts. Therefore, MAGPASS-COAT® is ideal for the coating of products in various sectors.
  • Mechanical engineering
  • Automotive industry
  • Electrical engineering
  • Aviation industry
  • Telecommunications
  • Motorcycle industry