Aluminum alloy oxidation is a widely used surface treatment method that enhances the durability and aesthetics of aluminum products. This process not only saves time and energy but also helps achieve excellent corrosion resistance, making it a favored option across various industries. However, the oxidation process alone is not enough to guarantee high-quality results. Post-oxidation treatment is crucial to ensure the longevity and appearance of aluminum alloy products. In this article, we will explore the key steps and best practices for handling aluminum alloy after oxidation to maintain product quality.
The Process of Post-Oxidation Treatment
1. Hot Water Cleaning
After the oxidation process, aluminum alloy products undergo hot water cleaning. The primary purpose of this step is to age the oxide film layer. Proper aging helps to solidify the coating, making it more resistant to environmental changes. However, this step requires strict control over water temperature and cleaning duration. If the water is too hot, or if the cleaning lasts too long, the film layer may thin out, and its color may fade. To avoid these issues, it is recommended to maintain a water temperature between 40 and 50℃ and limit cleaning time to 0.5-1 minute.
2. Drying
Drying is a critical step in the post-oxidation treatment process. The best method is to allow the parts to dry naturally. After hot water cleaning, the aluminum alloy products should be hung obliquely on racks, allowing the excess water to flow downwards. This ensures that the water does not stagnate, preventing streaks or spots from forming on the surface. A towel can be used to gently absorb any remaining water droplets, especially in corners. Natural drying helps retain the original color and quality of the oxidized layer, maintaining a clean and uniform appearance.
3. Aging
Aging is another important step in stabilizing the oxide layer after oxidation. Depending on the climatic conditions, aging can be done in two ways: exposure to sunlight or baking in an oven. In sunny weather, allowing the products to dry in direct sunlight is an efficient and cost-effective method. During colder months or rainy days, oven baking is preferred to ensure consistent results. The ideal process conditions for aging are a temperature range of 40-50℃ with a time duration of 10-15 minutes. This step further strengthens the film layer, improving its durability and resistance.
Dealing with Unqualified Parts
Despite careful oxidation and post-treatment processes, some aluminum parts may not meet the desired quality standards. It is essential to inspect these parts before the aging process begins. If parts are found to be defective after drying, the oxide film becomes much harder to remove, making it difficult to reprocess them. Early detection and handling of unqualified parts prevent the need for extensive rework, ensuring smoother operations and higher-quality end products.
Conclusion
Post-oxidation treatment is a crucial component of the aluminum alloy surface treatment process. Proper handling of each step—from hot water cleaning and natural drying to controlled aging—ensures that the aluminum products maintain their aesthetic appeal and durability. Additionally, early detection of unqualified parts saves time and resources in the long run. By following the best practices outlined in this article, manufacturers can produce high-quality, long-lasting aluminum alloy products that meet the expectations of even the most demanding customers.