umicore Electroplating gold cobalt electrolyte For the Adhesive Direct Gold-Plating of Stainless Steel and Nickel AURUNA® 311 is a strongly acidic alloy electrolyte for the adhesive direct gold-plating of stainless steel. It is preferably used for chromium-nickel steels, molybdenum steels and nickel based alloys difficult to activate. Due to its strong activation effect, the electrolyte can be often successfully used as well for other passive materials difficult to plate. The gold electrolyte is suitable for both strike gold layers and thick coatings in the decorative field. The coatings are ductile, low in pores and protect against corrosion. The alloy electrolyte can be used for rack and barrel operation as well as in reel-to-reel plating (e.g. spray and dip cells and brush). AURUNA® 311 is also available as a cobalt-free special version. Applications • Household articles • Writing implements • Spectacle frames • Watches • Cutlery Advantages • Hard gold electrolyte for the direct gold-plating of stainless steel • Very good activation effect - without halogenides • Low-pore, ductile and crack-free coatings • Suitable for strike gold layers as well as for thick coatings • Good throwing power • Available as a cobalt-free special version • The coatings are RoHS compliant • Suitable for rack, barrel and reel-to-reel plati

GOLD COBALT ELECTROLYTE TECHNICAL SPECIFICATIONS Electrolyte characteristics Electrolyte type Coating characteristics Strongly acidic Metal content pH value Operating temperature Current density range Plating speed Room temperature up to max. 40 °C 2 - 6 A/dm² 0.04 - 0.15 μm/min Pt-Ti, MMO (type PLATINODE® 177) Anode material Coating Alloy composition, approx. values Colour of deposit Brightness Hardness of deposit HV 0.015 (Vickers) approx. values Max. coating thickness Density of the coating Gold-cobalt 0.3 weight % Co 99.7 weight % Au Deep yellow Bright 165 HV Approx. 10 μm Approx. 17.5 g/cm³...