With the vigorous development of the aluminum processing industry, aluminum surface treatment has become an important production link in the aluminum processing process.
After the surface treatment of aluminum products, the functions of abrasion resistance, corrosion resistance, light resistance, weather resistance, etc. have been greatly improved, and more importantly, it is capable of carrying various beautiful and beautiful colors. In practice, due to differences in personnel, process, equipment, operation, etc., there will be certain differences in the color difference of each batch of products, and different quality defects occur. Under certain media, the color depth is caused by the accumulation of metal particles. Resolution, regardless of the thickness of the oxide film. The occurrence of the difference in the electrolysis of aluminum is directly related to the coloring mechanism, the uniformity of the thickness of the oxide film, and the structure and the electrochromic speed. The disadvantages of aluminum coloring generally have the following conditions: light color, color difference, dyeing, coloring, white spots, whitening, dyeing and fading, and escaping. How to deal with this problem, to ensure that the color difference of each batch of products adheres to the same, and within the scale of the error recognized by both sides, to satisfy the customer's requirements. This requires the manufacturer to study and prepare for the electrochromic surface treatment of the profile.
Common quality defects and treatment methods in the anodizing production process
First, we must evenly stabilize the color and control the color difference within a certain scale to reduce the occurrence of color defects. In the actual production process, firstly strengthen the operation of the anodizing process operation, pay attention to the following requirements during operation. .
1. When the anodized profile enters the coloring tank, it is necessary to adhere to a large inclination and place it in the middle of the north and south poles to ensure that the left and right pole pitches are level, and the area of the loading material is controlled together, and the total surface area per hanging material is not exceeded. 44m2.
2. Check the bath concentration to see if it meets the process requirements.
3. When the power is sent and colored, it is necessary to disconnect the driving hook and the conductive beam, and let it sit for 0.5 to 1 minute before sending the power to color.
4. The color voltage of the same color must be flat, and the power supply voltage should be adjusted before coloring.
5, at the end of the color, it is necessary to immediately hoist, quickly drain the tank, quickly transferred to the sink to wash, do not stay in the color tank, strictly control the air lifting time, fully wash the acid in the hole inside the profile, The color is used for colorimetric colorimetry. When colorimetric, the color of the profile is slightly deeper than the color of the sample. When the color is too light, put it into the color tank from the head to energize the color. When the color is too dark, put it into the color tank (not energized) from the head or the acid sink behind the oxidation tank to fade.
6, because the golden yellow can not fade, set the coloring time should not be too long.
7. After the coloring, the profile should be washed with acid water after the second-stage washing, and then it can be electrophoresed or sealed.
8. Strengthen the scouring before dyeing. After the workpiece is taken out from the anodizing tank, it should be washed thoroughly, especially the slits, blind holes, etc. of the workpiece. Otherwise, the remaining acid and alkali will slowly flow out during the dyeing process, so that the dyeing solution will be made. The pH value is contrary to the normal scale, and the color of the surface of the residual acid-base portion is significantly different from that of the cleaned portion, and even the oxide film is corroded to appear white.
9. Dyeing after anodizing, the workpiece should be dyed immediately after anodizing. If the workpiece is exposed to the air after being anodized, the pores of the film will shrink and the dirt may be stained, which may cause difficulty in dyeing. If the dyeing tank is too small and needs to be dyed in batches, the parts to be dyed should be immersed in clean water.
10. When the dyeing, the workpieces are not stacked, and the workpieces are not stacked when dyeing, especially the flat parts, otherwise the stacked parts are concealed to form the yin and yang.
11. Strengthen the scouring after dyeing. If the surface of the workpiece is not washed clean, leaving residual pigment will contaminate the assembly.