Barrel and rack plating electrolyte for functional applications
MIRALLOY® has been offering nickel-free plating for the connector, clothing and fashion jewellery industries for more than 30 years. You can benefit from our experience and the ongoing development of our product range. The trademark MIRALLOY® comes from the English words “mirror“ and “alloy“. It refers to the Bronze Age, when copper and tin were used to make mirrored alloys.
MIRALLOY® denotes electroplating processes for the deposition of alloy coatings of copper and tin or of copper, tin and zinc. Depending on the electrolyte used, white or yellow layers can be deposited. You can choose electrolytes for rack and barrel plating from the wide range of MIRALLOY® processes available.
Electrolyte characteristics
Electrolyte type Alkaline-cyanide
Metal content 8.5 g/l Cu 34 g/l Sn 0.75 g/l Zn
pH value > 13
Operating temperature 60 (58 - 62) °C
Current density range 0.5 (0.3 - 1) A/dm²
Plating speed 0.12 μm/min at 0.5 A/dm²
Anode material MMO (type PLATINODE® 167, graphite)
Electrical conductivity >50 m*(Ω*mm²)-1
Coating characteristics
Coating Copper-tin-zinc
Alloy composition 55 wt. % Cu 30 wt. % Sn 15 wt. % Zn
Colour of deposit white
Hardness 550 HV
Max. coating thickness 5 μm
Advantages
White layer, similar to silver
Diamagnetic
High reflectivity
Good wear and corrosion protection
Abrasion- and tarnish-resistant
Can be combined with precious metals
Good sliding properties
High hardness
Solderable and weldable
Very good metal distribution
Low porosity
Free from heavy metals like CR, Pb, Co, Th etc.
Low intermodulation
Platings are RoHS-compliant
Applications
High frequency connectors
Battery covers
Hydraulic parts
Contact pins
Cooling coils
Bearing shells
Conducting elements
