What is hard anodized aluminum?

Hard anodizing is a special type of electrochemical film-forming anti-corrosion in aluminum alloy anodization. The most significant difference from ordinary anodized aluminum is the oxide film thickness of the two: generally, the oxide film thickness of anodized aluminum is 5 -20μm, while the oxide film thickness of hard aluminum oxide is more than 50μm, and the maximum thickness can reach about 250μm.

The main purpose of hard anodizing treatment of aluminum alloys is to improve various properties of aluminum and aluminum alloys, including corrosion resistance, wear resistance, weather resistance, insulation and adsorption. It is suitable for both deformed aluminum alloys and die-cast aluminum alloy parts.

The difference between hard anodized aluminum and ordinary anodized aluminum

1. Oxide film thickness: The thickness of ordinary anodized film is 5-20um, and the thickness of hard anodized film can reach 50-200um.

2. Different hardness: the hardness of ordinary anodizing is HV250-350, and the hardness of hard anodizing is HV350-550.

3. The anodizing temperature is different: the temperature of hard anodizing is generally 5℃ and below. Relatively speaking, the lower the temperature, the higher the hardness; the temperature of the oxidation tank for ordinary anodizing is around 18-22℃, and with additives it can reach 30 ℃.

Features of hard anodized aluminum

1. 1. Ultra-high hardness: The hardness of aluminum products that have been hard anodized is greatly improved, which can effectively make up for the lack of hardness of the aluminum itself.
2. 2. Super wear resistance: The wear resistance of hard anodized film is usually 1-2 times higher than that of ordinary anodizing (except for 2 series alloys).
3. 3. Excellent electrical insulation: The resistance coefficient of the hard anodized film is relatively large, and its breakdown voltage can reach more than 1000V. After sealing treatment (dip in insulation or paraffin), the breakdown voltage can reach 2000V, and its electrical insulation is very good. good.
4. 4. Strong corrosion resistance: The corrosion resistance of hard anodized films is generally stronger than that of conventional oxide films. Adding coatings, paraffin, mineral oil, etc. after hard anodizing can further improve the corrosion resistance of the film.
5. 5. Excellent heat resistance: The hard anodized film has poor thermal conductivity and its melting point is 2050°C, making it an ideal heat-insulating film.

Applications of hard anodized aluminum

Hard anodized aluminum is mainly used in aluminum and aluminum alloy parts that require high wear resistance, heat resistance, and good insulation properties. Such as various inner walls of cylinders, pistons, steam plugs, cylinders, bearings, aircraft cargo compartment floors, roller rods and guide rails, water conservancy equipment, steam impellers, leveling machines, gears and buffer pads and other parts.

Original Source:https://www.flait-aluminum.com/Anodized-Aluminum-Sheet-Coil.html