Acid cleaner and etch for alloys containing high concentrations of magnesium and silicon
Liquid, immersion applications only, a blend of acids and surfactants specifically formulated for use in deoxidizing/desmutting of alloys of aluminium prior to chromating or conversion coating application. The ALUMAL DEOX 427 is designed to help the removal of some difficult residual soils and alloy constituents in the processing specifically of alloys containing high concentrations of magnesium and silicon.
Features & Benefits
- Single step process for desmutting all alloys, especially high Mg and Si alloys.
- One component liquid for ease of make up and replenishment.
- Cleans soils/smuts and removes oxide layers often obtained after prolonged exposures of metal to humid environments with minimal grain boundary attack on most aluminium alloys.
- Nitrate and phosphate free formulation
This process belongs toALUMAL DEOX series
Aluminium has a natural protective oxide surface film and affinity for oxygen, in order to improve the appearance of an aluminium part or component through conversion coating, painting, anodizing or plating processes, requires some additional surface treatment processing to remove the natural oxide layer.
Once aluminium and alloys are exposed to etching solutions, the oxides are often removed but then depending on the alloy of aluminium, there are surface adherent non-reactive reaction products referred to as “smuts” on their surfaces. Desmut formulations are required to remove these from the surfaces of aluminium parts or components. The types of smuts present are related to the alloy of aluminium. For example, 200 series wrought aluminium have resulting copper smuts that are effectively removed by iron based desmut formulations. Alloys containing silicon or magnesium smuts are thoroughly desmutted with blends of acids including fluorides, nitrates & sulphates. All surface smuts must be removed for success with applications of conversion coatings, painting, anodizing or plating aluminium and alloys.
Choices for Anodizing applications include ALUMAL DEOX 411, 436 or 444.
For chemical conversion coating prior to painting, review ALUMAL DEOX 411, 425, 445, or 427.
Coventya offers many additional types of ALUMAL products to effectively deoxidize and desmut all types of cast and wrought alloys of Aluminium. This is just a partial list of what is available; contact your local COVENTYA representative for review of other available technologies.