Views:0 Author:JIA HUA ALUMINIUM CO., LTD Publish Time: 2020-07-28 Origin:Site
Aluminum profiles after extrusion and ageing will be sent to do the surface finish. That is help the aluminum profile can get better corrosion and long life time. There are thousand of hundreds color for aluminum profiles. So sometime the customer may meet the problem of color difference. Especially the anodizing and electrophoresis finish. Here Jia Hua will show you how we control the color.
1. Anodized and electrophoresis
We should know why it comes the color difference in Anodizing at first. Some suppliers they use the vertical anodizing production lines. The depth of anodized slot have 7.5m long. Therefore, it is easy to get the different temperature in the top and bottom. Temperature is important to anodizing. If in a high temperature, the size of hole for the aluminum profiles will be increased.
Oxidation coloring is mainly to make the metal ions of the coloring liquid undergo an electrochemical reduction reaction on the surface of the barrier layer in the micropores of the oxide film, so that the metal ions in the coloring liquid are deposited on the bottom of the anodic oxide film hole to scatter incident light But showing different colors, the more substances deposited in the micropores, the darker the color. Under the condition of passing the same amount of electricity, the same amount of metal or metal compound is deposited on the high and low temperature parts. For the parts with high porosity and large surface pores, the average deposit per hole is less, so the color of the profile is relatively Lighter, darker on the contrary, resulting in two colors of the coloring material.
For horizontal production line, it also will have color difference if the worker cant vise the material in tight. This will make the aluminum profile poorly conductive. To avoid this problem, the worker we hire with rich experience. They know the processing of anodizing well. It’s good for the material upload for anodizing. And we will train our worker in a certain time to improve their efficient and Normative.
Our advance anodized and electrophoresis production line are control by the computer. Time, dry, temperature etc all are control by it. With this CNC control, it's good at prevent the Misoperation and improve the efficient.
After the anodizing, there will have 2-3 QC to check the quality before packaging. They will use the Colorimeter to check the color. And they will use the color sample to compare the color.
At last, QC in the lab will Random inspection some PCS of the order to double check. It can help to find out whether there are else problem.
2. Powder coating aluminum profile:
We usually think powder coating finish will have no color difference. But actual is not. If the worker don’t clean spray machine when they change the color. There will have some Powder residue on the spray machines. And then the next color will mix some powder of last color. That will make the color difference. Beside, if suppliers use cheap and lower quality powder, it also have quality problem.
You will find there are a manager of color. He will help to check the powder and color, the supplier sent to us. He will ask the worker to test some powder with sample. And take sample to lab for check the quality and color. If there are any problem for the powder, we will ask the supplier to reproduce it. Actual, a trust supplier of powder, they also will check the quality before send the powder to us. The supplier we cooperate is famous in Foshan city, Guangdong province. And we will also have cooperation with Aksu powder factory. Control the quality from the source can help you save many times. After powder coating, we also have QC to check the color. Any problem should be found before packaging.
For the color, we are careful to handle it. We will make a sample to customer for confirm before the mas production. And we will compare the color with this sample during production. Jia Hua always think in customer’s way to help them get the good quality products.