Hard oxidation and ordinary oxidation difference: Hard anodized oxide film has 50% penetration inside the aluminum products, an another 50% attached to the aluminum workpieces surface, so after a hard anodizing exterior of the product size becomes bigger, the hole becomes smaller, while after hard oxidation the external dimensions of ordinary oxidation becomes smaller and the hole becomes bigger.
Hard oxidation colors:
Hard oxidation colors usually made of black and oxidation film true colour (natural color), true color is determined by the aluminum alloy composition, even the same type of aluminum ( for example 6061-T6), and different manufacturers, the color of the oxide film is different, if Aluminum use same manufacturer the same type of material maybe colors are different, and therefore, the true nature of the oxide film is generally used for the internal parts of the product.
Hard oxidation aluminum advantages:
1, Aluminum hard anodizing surface hardness can even up to HV500, which can compare to chrome plating;
2, The hard anodizing film thickness from 25 to 250um;
3, Have features of strong adhesion, according to the generated hard anodized oxidation characteristics: hard oxidation film has a 50% penetration in aluminum inside,
50% adhered to the surface of an aluminum alloy;
4, Good insulation: breakdown voltage up to 2000V;
5, Great wear resistance: for if copper content more than 2% in aluminum alloy, its maximum wear index of 3.5mg/1000rpm. All other alloys wear index should not exceed than 1.5mg/1000rpm;
6, Non-toxic: the oxidation film and for anodic oxide film produced by an electrochemical process there is no toxic to humans.
So now a lot of industry in order to facilitate machining and reduce the weight of products, and environmental protection requirements, some hard oxidation aluminum alloy parts products are currently to replace stainless steel, and conventional spray, plating treatment process.
Hard oxidation real case:
This customer use our Hard oxidation pulse power supply for aluminum pot hard oxidation, the result is very good. You can see the below surface, the hardness also very good, there is no any scratch on surface even use a knife to cut the aluminum pot hard anodizing surface.
2000A90V Hard oxidation rectifier, using our power supply you can get very good treatment even 2 & 7 series aluminum grade.