Reasons Why The Surface Of Aluminum Alloy Parts Become Black

Aluminum oxide processing aluminum alloy castings are generally made of metal molds. Metal aluminum and aluminum alloys have good fluidity and plasticity, but they are easy to turn black during use. The reasons are:

(1) The process design is unreasonable. Improper handling of aluminum alloy die castings after cleaning or pressure inspection creates conditions for the aluminum alloy die castings to become black and mold, and accelerates the formation of mold.

(2) Warehouse management is not in place. If the aluminum alloy die castings are stored at different heights in the warehouse, the moldy conditions are also different.

(3) Internal factors of aluminum alloy. Many aluminum alloy die-casting manufacturers do not perform any cleaning treatment after die-casting and machining processes, or simply flush with water, which cannot be thoroughly cleaned. The surface of die-cast aluminum has corrosiveness such as mold release agent, cutting fluid, saponification fluid, etc. Substances and other stains, these stains accelerate the speed of black spots of aluminum alloy die castings.

(4) External environmental factors of aluminum alloy. Aluminum is an active metal, and it is easy to oxidize and turn black or mold under certain temperature and humidity conditions, which is determined by the characteristics of aluminum itself.

(5) The use of cleaning agents is not appropriate. The selected cleaning agent is highly corrosive, causing corrosion and oxidation of die-casting aluminum.