Anodizing bathtub contains a certain amount of sulfuric acid with normal density (H2504) which is connected to electric current by a rectifier in anodizing bath tube,cathode is the aluminium wall of the bath tube and anode are the parts.So they are from the same material(and as a result you will have an ideal anodizing process).
According to galvanic table although ,Al is a reactive metal which is exposed to corrosion too fast but aluminium oxide will be (Al203) formed as a resistant and sticky layer, so AL corrosion will be stopped, and then in anodizing process and by electric current in an acidic environment the layer thickness increases and results in formation of shining and limpid surface on AL parts. based on customer demand and after anodizing process, the anodized parts will be snaked in steel paint bathtubs (to have better electrical conduction and throw stuff), and after washing in boiling water will be conveyed to dryer to be prepared for packing at the end. we are able to anodize AL parts in different colors such as silver, gold bronze and black our research and development department is trying to establish an anodizing line for red , blue and other colors too. for increasing the quality and removing sediments, salts, annoying cathodes and anodes,all bedding, anodizing, washing and neutralizing bath tubes will be charged by deionized distilled water (Ph=7).a|| used chemical materials are supplied from original brands (Henkle from Germany, Italy and etc). our anodizing and bedding units are equipped with 22 bath tubes with the capacity of 16000 liters so SRPA is able to anodize 2000 tons of up to 6/50m length AI parts.