Zinc nickel plating has the ability to offer outstanding corrosion protection, especially when subjected to high temperatures. It is used extensively in automotive under body applications where its temperature and corrosion resistance are vital.
The preferred alloy composition of zinc nickel plate is 12 – 15% nickel, with the remainder being zinc. This alloy gives exceptional sacrificial corrosion resistance and can be readily passivated. To achieve this alloy, zinc nickel is usually plated from an alkaline electrolyte.
Zinc Nickel is used to plate steel components when they are to be assembled with other dissimilar metals, particularly aluminium, and where there is a greater risk of galvanic corrosion. The plating layer is extremely ductile which enables pipe and tube assemblies to be plated prior to manipulation into their final shape. Its corrosion protection can be enhanced with clear, yellow or black Trivalent passivates.
Key Properties for Zinc Nickel Plating
• Corrosion Protection
• Typical Rack plated component with colour passivate – 1000 hours to White corrosion, 1500 hours to red corrosion (neutral salt spray)
Abrasion resistance – harder than normal Zinc plating systems
• Automotive – Fluid transfer tubes which can be deformed into their required shape after plating
• Automotive – Fasteners, particularly in areas of high corrosion (under hood, chassis joints)
• Electronic – Connectors, as a direct replacement for cadmium to provide corrosion resistance and high electrical conductivity.
• Aerospace & Defense – joining components in contact with aluminium