Aluminum oxidation common problems and solutions

One, can not dye color

1.Insufficient anodic oxidation film thickness. The solution is to check whether the anodic oxidation process is standardized, to see whether the temperature, voltage, conductivity and other factors are stable, if there is an anomaly, please adjust the specification accordingly, if there is no anomaly, the oxidation time can be appropriately extended to ensure that the film thickness is up to standard.

2, the pH value of the dye is too high, at this time, the pH value can be adjusted to the standard value of glacial acetic acid.

3.The workpiece is placed in the sink for too long after oxidation. Promote timely dyeing, if this has happened, the workpiece can be placed in the anodic oxidation tank or nitric acid neutralization tank appropriate activation treatment before dyeing, the effect will be very good.

4, improper selection of dyes. Suitable dye should be selected.

5, the dye has been decomposed or mildew, at this time need to replace the dye.

6, the oxidation temperature is too low, resulting in dense skin film. The oxidation temperature can be appropriately increased.

7.Poor conduction. May be anode copper rod or cathode lead plate poor contact, indicating poor batch conductivity. Pay attention to cleaning the anode copper rod and the cathode lead plate to ensure good contact.

Two, white spots, exposed white

1, washing is not clean, should strengthen washing.

2.The water used for washing is too dirty and easy to pollute the skin film. At this time, the water should be replaced to ensure the quality of washing.

3.The oxide film is polluted by smoke, acid and alkali fog in the air. Intensive washing, timely staining and timely transfer can greatly reduce this symptom.

3.The oxide film is polluted by oil and sweat stains. Protection must be strengthened, and the appearance of the workpiece must not be touched by hand.

5, there are insoluble impurities in the dye, contaminated by oil, destroy the normal dyeing, at this time should be filtered or replaced.

6, the workpiece gap, deep hole in the residual acid flow out, to strengthen the washing of such workpiece.

7, the dye is contaminated by Cl-, resulting in point corrosion of the dyed workpiece, at this time must replace the dye, usually should pay attention to avoid the introduction of impurity ions in the operation process.

Three, color light, color difference

1.Uneven thickness of skin film. The possible reason is that the temperature and concentration of the anodic oxidation tank are uneven, and the tank should be stirred by compressed air to greatly solve such problems.

2.Uneven temperature or concentration of dye solution. Mixing process is introduced.

3, dyeing speed is too fast. The bottom of the workpiece first enters the dyeing liquid and finally leaves the dyeing liquid, so the bottom is the most easily dyed deep. The solution is to dilute the dye and extend the dyeing time appropriately.

4,Poor conduction. It may be caused by loosening of the hanger, pay attention to the hanging can avoid such problems.

5, the dye is too thin, you can add dye to improve the concentration.

6, the dye temperature is too low. The dye can be warmed to below 60℃.

7, improper dissolution of dyes, or insoluble dyes floating, which is easy to produce color difference. The solution is to improve the dye dissolution.

Four, dyeing hair flowers, escape color

1.The pH value of the dyeing solution is low, and the dilute ammonia can be adjusted to the standard value.

2. cleaning is not clean. Water washing should be strengthened.

3. the dye is not completely dissolved, strengthen the dissolution to completely dissolve.

4.the dye temperature is too high, reduce the temperature.

5.The pores of the oxide film are small, because the oxidation temperature is too low, which prevents the skin film from being dissolved by sulfuric acid, and the oxidation temperature can be appropriately adjusted to avoid this problem.

6. the dyeing is too fast, and the dyeing time is too short, can be adjusted to dilute the dyeing solution, reduce the dyeing temperature, and appropriately extend the dyeing time.

7.sealing temperature is too low, heating solution.

8.The pH value of the sealing solution is too low, adjust it to the standard value with dilute ammonia.

9.The stained surface is easy to erase. The main reason is that the skin film is rough, which is generally caused by too high oxidation temperature. Attention should be paid to controlling the oxidation temperature within the standard range.