Passivation for casting parts (alu,zinc parts)


aluminum alloy casting with passivation

Many aluminum alloy and zinc alloy die-casting parts have been widely used due to their advantages of easy processing, high precision, and certain mechanical strength. However, these castings have the disadvantages of negative potential and poor corrosion resistance. Therefore, for aluminum alloys with high corrosion resistance and decorative properties, zinc alloy die castings are often coated with multiple layers on the surface.


For some aluminum alloys and zinc alloy parts with good working conditions and no special requirements, they can be directly polished and passivated, and the parts after passivation have the same beautiful layer as the zinc plating after passivation, and the corrosion resistance is also blunt. There is a big improvement before the change.


Aluminum alloy can be treated with a variety of surface treatments. Passivation is one of the surface treatments of aluminum alloys. It forms a very thin protective layer on the surface of aluminum alloy under specific chemical action. Good, and can make the parts anti-oxidation, the general thickness is relatively thin, the passivated color is generally the product color, in the electromechanical aluminum parts, especially the ship-related cast aluminum parts, some special cast aluminum furniture parts, fluid parts, etc. Has a very wide range of applications.


After the passivation treatment, it has the characteristics of not increasing the thickness of the workpiece and changing the color, improving the precision and added value of the product, and making the operation more convenient;


Passivation characteristics:
1. Excellent corrosion resistance, usually well working for casting aluminum in: ADC12, ADC6, A356, A380, etc. neutral salt spray for more than 360 hours, meets or exceeds the corrosion resistance standards of MIL-DTL-8170 and MIL5541F.

2. Can be used for aluminum alloy and aluminum die casting.

3. Form a transparent, natural film layer. The film layer has a low contact resistance of less than 0.8 mOhm/cm2 and is resistant to high temperatures.

4. Environmentally friendly, safe and non-toxic, in line with ROHS, ELV, WEEE regulations. Waste water treatment is simple.

5. Suitable for dipping, spraying, and hand wiping.