Surface defects on aluminium ingots are not just cosmetic. They are a signal that something in your casting line is out of control. Cold shuts mean the metal is too cold. Oxide skin means the metal is exposed to air too long. Surface porosity means hydrogen is too high. Cracks mean the cooling is too fast or too uneven. I have spent 25 years troubleshooting aluminium ingot casting lines in China, Southeast Asia, India, Europe, and North America. Surface defects...
