How to prevent the formation of mold marks on extruded aluminum profiles?

Mold marks are longitudinal unevennesses on the surface of aluminum alloy products, and all extruded aluminum products have varying degrees of mold marks. The main cause is that the working belt of the mold cannot achieve absolute smoothness, resulting in defects that mostly recess into the extrusion surface and can be seen with the naked eye.

Causes of Mold Marks on Extruded Aluminum Alloy:

(1) Poor cleanliness and smoothness of the mold surface;

(2) Insufficient hardness of the mold surface, which easily sticks to aluminum;

(3) Foreign objects adhere to the surface of the mold working belt.

Preventive Measures for Mold Marks on Extruded Aluminum Alloy:

(1) Check the mold working belt for scratches, smoothness, and cleanliness;

(2) Nitriding treatment should be applied to the mold, ensuring high and uniform hardness on the working belt surface;

(3) Inspect the surface of extruded parts promptly to identify scratches;

(4) Prevent foreign objects from sticking to the mold and remove them in a timely manner;

(5) The mold working belt should be uniformly processed, polished smooth, and proper operation should be ensured.