Isolation strategies for fastening steel bolts on magnesium components include the use of aluminum shims and spacers. NANOMYTE® PT-60, a patent-pending conversion coating with active corrosion protection functionality, presents an alternative where the cost associated with spacers can be avoided without sacrificing performance. Neutral salt spray testing of PT-60 treated magnesium, with a standard epoxy primer, exhibits better performance than the current practice. Tests show enhanced protection against galvanic corrosion between zinc plated steel bolt and magnesium substrate. Additionally, PT-60 significantly reduces general corrosion. Minimal corrosion build-up at the scribe demonstrates the self-healing corrosion inhibition mechanism at work.
PT-60 is a chromate-free, self-healing conversion coating for magnesium that is a drop-in replacement for chromate. It can be applied as a thin conversion coating that protects the metal from corrosion, or as a pretreatment that improves adhesion with overlying paint.