Additive for Improved Performance of Sulfuric Aluminium Anodising

Liquid additive for sulfuric anodize systems that improves the layer performance and the efficiency of the anodize process.  Operating temperatures up to 30°C can be utilized while increasing the solution tolerance to dissolved aluminium is possible.  Layer quality is improved by increasing hardness, brightness, colour penetration and efficiency of the sealing process.

The development of ALUMAL ELOX 557 additive for sulfuric acid anodizing systems allows applicators to increase the performance of the resulting oxide layer and efficiency of the anodizing application.  The quality of the resulting oxide layer is improved by increasing the hardness and resulting wear resistance, ductility, colour ability and efficiency of the sealing process.  Electric energy savings up to 15-25% can be realized due to lower applied voltages, while processing time is reduced as the oxide layer can form 15 – 25% faster using the ALUMAL ELOX 557 additive.  The consumption of sulfuric acid is also reduced because of the inhibiting effect of the additive on the dissolution of the oxide.


Features & Benefits

  • Increases hardness of anodic oxide layers up to 75 – 85 HV units over conventional sulfuric anodize systems, resulting in improved wear performance
  • The anodic oxide layer is less brittle, despite of its hardness, than the oxide obtained without using the additive.
  • Changes the micro-structure of the oxide by increasing the number of smaller pores, which yields a more even structure, higher gloss and smoother surface finish.
  • Electro-colouring and/or organic colouring processes are easier to control/manage – resulting colour resistance is better, resulting from improved colour penetration in the pores.
  • Sealing process is simplified, as smaller pores are filled, for cold sealing the consumption of the sealing additives are decreased up to 10%.
  • Ability to anodize at higher temperatures (up to 240C) and lower voltages (about 1 – 2 Volts lower), less heat generation provides savings of electric energy for cooling up to 30 – 50%
  • Operating at higher dissolved aluminium concentrations (up to 27 g/L) which extends the solution life of the anodizing solution and requires less solution replacement.
  • Savings of sulfuric acid consumption up to 40% (100 grams/m2) due to decreased dissolution rate and reduced frequency requirement of solution replacement.
  • Anodizing solutions containing ELOX 557 can be used as replenishment for desmut since anodizing chemistries containing oxalic acid cannot be used in this fashion

This process belongs toALUMAL ELOX Series

Anodizing aluminium and alloys is an important electrolytic passivation process utilized across many industries to increase the performance of parts fabricated from alloys of aluminium or to improve the appearance of their surfaces.

This can be accomplished through increasing the thickness of the natural oxide layer on the surfaces of parts and components. COVENTYA offers complete processes for Sulfuric acid type anodizing, and more importantly some additives for the anodizing chemistry that provides many benefits to applicators who process aluminium parts and components.

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