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As is well known, the anodized coating on aluminum alloys can significantly improve the surface properties of these alloys, particularly important properties such as surface hardness, corrosion resistance, and wear resistance, which are related to their service life. Therefore, the anodized coating is regarded as a \"versatile\" surface strengthening method for aluminum alloys. The rapid pace of development is evident, from importing simple small horizontal anodization production lines with an annual capacity of 3,000 tons 20 years ago, to the current operation of multiple large vertical anodization lines with an annual capacity of over 30,000 tons. Through continuous elimination, selection, integration, and improvement, China’s aluminum alloy building profiles now feature three main series of surface treatment technologies: anodizing, anodized electrophoretic coating, and organic polymer electrostatic spraying. The development direction and level of these technologies are in line with international standards, with equipment capabilities, process characteristics, and product quality all reaching advanced international levels. As early as the mid-1980s, China’s aluminum profile industry was in its infancy. In 1986, the Science and Technology Bureau of China Nonferrous Metals Corporation drafted a document titled \"Methods and Criteria for Testing the Properties of Anodized Coatings on Building Aluminum Profiles\" based on the suggestions of various experts. This document played a crucial role in standardizing product quality and promoting the development of production at that time. The document recommends testing 6 performance criteria: (1) visual color difference; (2) oxide film thickness; (3) sealing quality; (4) salt spray resistance; (5) wear resistance; and (6) lightfastness (color fastness). Due to the limitations of technology and equipment at that time, specific requirements were set only for the first 3 tests. Corrosion resistance, wear resistance, and light resistance are merely conceptual terms; specific methods for performance testing, test parameters, as well as criteria for accepting performance levels are not specified. It seems that the content of this document may not be yet perfect, but 20 years ago it was already clearly stated that the thickness of the anodized coating and the quality of its sealing are essential properties; these are what are now considered to be mandatory testing parameters for the performance of anodized coatings. Over the past 20 years, China’s aluminum profile industry has developed rapidly. The technical requirements regarding the properties of anodized coatings, as well as the acceptance criteria and testing methods, are well-defined. The corresponding **standards have been improved and refined, bringing them in line with those of various advanced industrial **countries. Therefore, the current performance testing items and methods need to be updated and expanded in order to keep up with the development of production in our country, as well as to more comprehensively and systematically align with international advanced technology levels and international standards. In 2004, the China Non-ferrous Metals Standardization Committee organized a series of performance testing experiments. Together with the South China Non-ferrous Metals Quality Supervision and Inspection Center, as well as six companies including Jianmei, Nanping, Xingfa, and Minfa, these entities participated in comprehensive tests of the performance of products that were manufactured regularly in factories, rather than those produced specifically for testing purposes; as a result, nearly 20,000 data points were collected. The experimental results have been compiled into a volume by the National Non-ferrous Metals Standardization Committee. Although the product quality in our country varies across different regions, it has generally seen significant improvement. Test data show that the products manufactured by these factories are on par with international advanced standards; therefore, it can be said with pride that China’s aluminum building profile industry is not only a large-scale industry but also a truly powerful one. Film thickness uniformity and sealing quality: The thickness of the anodized film is one of the most important performance indicators; it may even serve as an indicator of the service life. Sealing quality, on the other hand, is an important indicator of the corrosion resistance of the oxide film. Tests show that the variations in the data from the phosphoric-chromic acid weight loss test fall within the range of 6% to 15%; in other words, the deviations in the data related to corrosion-induced weight loss of phosphoric-chromic acid remain within 15%, which can be considered an acceptable level of measurement error. The upcoming new standard 8013.1 specifies that for the quality of sealing the anodized coating on aluminum alloy building profiles, the nitric acid pre-treatment followed by phosphochromic acid test is to be used as the arbitration test, as required by the European standard EN12373.6:1999. Experimental data show that the worse the quality of the sealing, the greater the effect of weight loss resulting from nitric acid impregnation; therefore, nitric acid impregnation is more sensitive in identifying and screening whether the sealing quality meets the standards based on the weight loss indicator of phosphoric-chromic acid. Post-treatment of cold sealing can significantly improve the quality of sealing and speed up the sealing process. Tests have shown that if post-treatment with cold sealing is carried out (i.e., immersion in pure water at 60–80°C for 10 minutes), the aging time can be shortened, allowing the sealing quality to reach an acceptable level rapidly. Other domestic and international tests have also shown that post-treatment of cold-sealed holes can significantly improve the plasticity of the anodized film on these holes, enabling them to withstand subsequent mechanical deformation without cracking. The CASS test for the corrosion and weather resistance of anodized films is a conventional test method for salt spray corrosion resistance. Tests have shown that the results of the CASS test on the anodized film do not always correspond exactly to those of the sealant quality, as sealant quality indicates the average corrosion rate, whereas the CASS test reflects the results of localized corrosion. Especially for the anodized film on mechanically sandblasted surfaces, it often happens that even if the sealing quality is satisfactory, the sample fails to pass the CASS test; when comparing the ratings obtained from the CASS test with those from the alkali washing process for the same samples, the corrosion level is 1 to 2 grades lower. The microstructure of the sandblasted samples may exhibit an increased sensitivity to local corrosion, as the anodic oxide film in the pits formed by sandblasting is incomplete. The alkali drop test method for anodized films needs improvement. The error in determining the end point for visual bubble detection as specified in GB5237 is quite large; it seems inappropriate to continue using this standard, and it should be revised. Even if data obtained using Japan’s resistance measurement method are used in the future and the accuracy is improved through the \"approximation method,\" it will still be difficult for the results of the alkali drip test to correspond exactly with those of the phosphoric-chromic acid sealing quality test or the CASS test. Given that the alkali drop test for anodized films is only specified in Japanese standards, and this method is not included in international or European standards, the necessity of the alkali drop test remains questionable. Weather resistance of colored anodized films. The electrolytically colored bronze anodized film shows that, according to tests, the color difference after exposure to ultraviolet radiation can be maintained at ΔE