Difficulties in Aluminum Alloy Processing and Their Solutions - Casting Defects (Scratches)

• Feature: There are linear scratch marks on the casting surface in the direction of mold opening, with a certain depth. In severe cases, the entire surface is scratched; the molten metal adheres to the mold surface, resulting in material deficiency on the casting surface. 

• Causes: There is damage on the surface of the mold cavity; The ejection direction has no slope or the slope is too small; The ejection is unbalanced; The mold is loose; The casting temperature is too high or too low, causing the alloy liquid to adhere; The effect of the release agent is poor; The iron content of the aluminum alloy is lower than 0.8%; The cooling time is too long or too short.