We gave careful consideration to selecting what we believe is the optimal process. Acidic and alkaline zinc-nickel coatings and alternative corrosion protection treatments – for example those that omitted nickel and were purely zinc-based – were ruled out following comprehensive testing before we opted instead for a zinc-nickel either acidic or alkaline galvanic treatment based on the fitting design. The process involving a new processing sequence and new layer composition was the only one to meet our high standards in terms of corrosion protection.

First an approx. 8-µm-thick zinc base coat with a 12-15% nickel content and extremely homogeneous ZnNi molecule distribution is galvanically applied. Additional passivation with a layer thickness of around 500 nanometers is then subsequently applied, before a final 2-µm-thick sealing layer. These layers make the difference, protecting the ZnNi surface and consequently prolonging its corrosion-protective effect. The ZnNi layer is applied with a significantly improved chemical efficiency factor of approx. 98%. As a consequence, the problem of increased hydrogen formation is minimised. In comparison: the conventional process with its poor efficiency factor of just 40% or so can result in embrittlement of the substrate.