Pock is the surface density in the range profile, with a tail, very small nodules, feel clear, there is the feeling of spikes.
Analysis of the main reasons
As the ingot inclusions or mold metal or stick to bring the work of debris, when high temperature and pressure in the extrusion of aluminum carries off, the profile surface Pock.
Solution
① appropriate to reduce the extrusion speed, extrusion temperature and the use of reasonable mold temperature;
② strict control of ingot quality, lower inclusion content in the ingot, the ingot to homogenization;
③ enhance the quality of the repair mode management.
