Top aluminum anodizing company

Carsai is a top aluminum anodizing company

The principle of anodic oxidation of aluminum is essentially the principle of hydrolysis. When an electric current passes through, the following reactions occur:   

At the cathode, H2 is released by the following reaction :2H + + 2e → H2   

At the anode, 4OH-4E → 2H2O + O2, the oxygen precipitated is not only molecular oxygen (O2), but also atomic oxygen (O), and ionic oxygen (O-2), usually expressed as molecular oxygen in the reaction.   

Aluminum as anode is oxidized by oxygen precipitated on it, forming anhydrous Al2O3 film: 2AI + 3[O] = AI2O3 + 1675.7KJ It should be noted that not all of the oxygen generated with aluminum, part of the precipitation in gaseous form.   

Types of anodic oxidation Anodic oxidation has long been widely used in industry. There are many methods under different names, which can be summarized as the following classification methods:   

According to the current type, it can be divided into direct current anodic oxidation, alternating current anodic oxidation, and pulse current anodic oxidation which can shorten the production time to reach the required thickness, the film layer is thick and uniform and dense, and the corrosion resistance is significantly improved.   

According to the electrolyte: sulfuric acid, oxalic acid, chromic acid, mixed acid and organic sulfonic acid solution of natural coloring anodic oxidation.   

According to the properties of the film layer, there are ordinary film, hard film (thick film), porcelain film, bright modification layer, semiconductor barrier layer and other anodic oxidation.   

The application of direct current sulfuric acid anodic oxidation method is the most common, because it is suitable for aluminum and most of the aluminum alloy anodic oxidation treatment; Thicker film layer, hard and wear-resistant, sealing hole can obtain better corrosion resistance; The film layer is colorless and transparent, with strong adsorption ability and easy coloring; Low processing voltage, less power consumption; The processing process does not need to change the voltage cycle, which is conducive to continuous production and practical operation automation; Sulfuric acid is less harmful to human body than chromic acid, with wide supply and low price.