Anodizing: Corrosion on Hardcoat Anodized 7000 Series Forging
Q. I sent you photos of two parts that are alloy 7050 forgings. On these parts there are spots that appeared as a result of Type III (hardcoat) anodizing that were not present before anodizing. They look like corrosion of some sort, but the corrosion looks a little different on each part. What causes these spots to appear and what measures can be taken to prevent or eliminate them after they occur?