AURUNA® 311 For Technical Applications Gold Cobalt Electrolyte

AURUNA® 311 For Technical Applications Gold Cobalt Electrolyte

For the adhesive direct gold-plating of stainless steel and nickel

AURUNA® 311 For Technical Applications 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 nickelbased alloys difficult to activate. Due to its strong activation effect, the electrolyte can be often used successfully as well for other passive materials difficult to plate.

The gold electrolyte is suitable for both strike gold layers and thick coatings in the technical field. The coatings are ductile, low in pores and protect against corrosion.

AURUNA® 311 For Technical Applications can be used for rack and barrel operation as well as in reel-to-reel plating (e.g. spray and dip cells and brush).

Electrolyte characteristics

Electrolyte type

Strongly acidic

Metal content

2 (1 - 10) g/l Au

pH value

0.6 (0.1 - 0.8)

Operating temperature

25 (20 - 40) °C

Current density range

2 - 6 A/dm²

Plating speed

0.08 μm/min at 2 g/l Au, 2 A/dm²

Anode material

Pt-Ti, MMO (type PLATINODE® 177 )

Coating characteristics



Alloy composition

Approx. 99.7 weight % Au 0.3 weight % Co

Colour of deposit

Deep yellow




160 HV

Max. coating thickness

10 μm


  • Strongly acidic gold alloy electrolyte for the direct gold-plating of stainless steel and nickel
  • 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
  • The coatings are RoHS compliant
  • Also available as a cobalt-free special version
  • Suitable for rack, barrel and reel-to-reel plating


  • Electrical contacts
  • Stainless steel contacts
  • Stainless steel springs


  • Produktblatt-auruna-311-for-technical-applications-en-screen-20190416.pdf

Your contact person

Markus Legeler

Manager Sales International
T: +49 7171 607 204
F: +49 7171 607 316

Find a representative in your region


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