Under normal circumstances, when testing the sealing quality of anodized aluminum profiles using the nitric acid pre-impregnation phosphochromic acid method, there are clear industry-standard and actual testing results regarding the weight loss range.
The official standard requires an upper limit for weight loss: According to domestically accepted testing standards, and consistent with EU QUALANOD and US AAMA 611 standards, the weight loss after sealing the anodized film using this method is generally no greater than 40 mg/dm².
Common performance in actual production: Based on batch sample testing data from domestic aluminum profile companies, 95% of qualified products show a weight loss of less than 30 mg/dm². Most high-quality anodized aluminum profiles produced in regular mass production have an actual weight loss controlled within the range of 20-30 mg/dm².