Aluminum alloy castings are the use of metal casting. Metal aluminum and aluminum alloys have good fluidity and plasticity, but they tend to turn black in the end.
The process design is unreasonable. Improper handling of die castings after cleaning or pressure inspection, resulting in rapid mold growth.
Warehouse management is not in place. Die-casting parts are stored at different heights, and mold conditions are unequal.
The internal factors of aluminum alloy. The die-casting manufacturer did not do any cleaning after die-casting and CNC, or just rinsed with water. Mold release agent, cutting fluid, saponification fluid, and other stains remain on the surface of die-cast aluminum. These stains accelerate the blackening of the die spots on the die casting.
The external environmental factors of aluminum alloy. Aluminum is easy to oxidize and become black or moldy under certain temperatures and humidity.
Improper choice of the cleaning agent. The selected cleaning agent is highly corrosive, causing corrosion and oxidation of die-cast aluminum.