As we all know, aluminum is an active metal, which is often oxidized and blackened under certain temperature and humidity. Therefore, when aluminum alloy die casting, if the post process is not handled properly, it is very easy to cause the blackening of aluminum castings. According to the characteristics of aluminum castings, effective measures are taken to prevent various causes of blackening of aluminum castings:

1. Process control

If the pressure is not enough during die casting, the density of the workpiece will be reduced and pores will be formed. After the water absorption of pores is oxidized, it is very easy to blacken. Therefore, the speed and strength of die casting will be effectively controlled to prevent it.

2. Surface cleaning

After die casting and machining, corrosive substances such as release agent and cutting fluid will remain on the surface of aluminum castings. Incomplete cleaning will accelerate the blackening of aluminum castings. Passivation treatment, including 6 cleaning processes such as pre degreasing degreasing water washing acid pickling water washing water washing, is adopted to reduce the risk of oxidation blackening of castings through effective cleaning.

3. Process control

Northern aluminum casting manufacturers require workers to wear gloves to avoid direct skin contact with aluminum castings. At the same time, pay attention to the drying of the product to prevent water stains from remaining on the surface of the object.

4. Storage and packaging

Place in a ventilated and dry environment and avoid direct sunlight. Open hole packaging is selected, which is easy to volatilize water droplets, and moisture-proof agent is added in the packaging box.

Editing: WMM