Vacuum Plating Production Process And Defective Analysis (2)

Defective 5. Electroplating semi-transparent

Description:

The translucent and pinhole light transmission properties are similar, and they also occur on PC transparent or translucent materials that require cover mold plating. When illuminated with light, the light passes through the coating position.

Analysis of the causes:

1. The amount of aluminum wire in the plating furnace is too small to form semi-permeability

2. The current through the tungsten wire is set too small in the plating furnace

3. The vacuum pressure in the electroplating furnace is too high

4. Air leakage in a vacuum furnace

5. Insufficient coating time

Key points of quality control:

1. The amount of aluminum wire in the plating furnace is too small to form semi-permeability 2. The current through the tungsten wire is set too small in the plating furnace
3. The vacuum pressure in the electroplating furnace is too high
4. Air leakage in the vacuum furnace
5. Insufficient coating time

Defective 6. Plating Burnt/Black Plating

Description:

The yellowing or whitening of the surface of the coating is obviously different from that of the standard plate.

Analysis of the causes:

1. There is air leakage in the vacuum furnace

2. The coating time is too long

3. The vacuum pressure of the vacuum furnace is too high

4. The current passing through the tungsten wire is too strong

5. There is a fault during the operation of the equipment

Key points of quality control:

1. Confirm whether the pressure gauge can reach the set standard pressure during the operation of the vacuum furnace.

2. Confirm whether the actual current parameters are consistent with the "Operation Instructions", and require adjustment if they do not match.

3. Confirm whether the pressure gauge parameters are consistent with the "Operation Instructions", and require adjustment if they do not match

4. Confirm whether the parameters in the benchmark book are consistent with the actual parameters, and require adjustment if they do not match.

5. Regularly check whether the equipment is inspected and maintained as required, and confirm the maintenance records

Defective 7. Accumulated oil

Description:

Oil deposits generally appear in the product； Edge or angular position, commonly known as runny oil. target； Depending on the hypertrophy, there is a feel.

Analysis of the causes:

1. Improper spraying technique, too thick spray film

2. Not drying in time after spraying, too long standing time

3. The viscosity of paint spraying is too low

4. The oil volume and air pressure of the spray gun are too high

Key points of quality control:

1. In the production process, confirm whether the spraying times and the distance of the spray gun are consistent with the "Operation Instructions", and compare and confirm with the sample during the production process

2. Supervise the spraying of UV primer, and it needs to pass UV within 6 minutes after spraying

3. Confirm the paint before production, and deal with the bad paint in time

4. During the process inspection, confirm whether the spray pressure is within the standard range of the "Working Instructions"

Defective 8. Thin-oil

Description:

Contrary to oil accumulation, it is mainly caused by uneven local spraying, showing orange peel, dense pinholes and other phenomena.

Analysis of the causes:

1. Improper spraying technique, too thin spraying film thickness

2. Too high spraying viscosity, which is not conducive to operation

3. The fuel volume of the spray gun is too small / the air pressure is too small

Key points of quality control:

1. In the production process, confirm whether the spraying times and the distance of the spray gun are consistent with the "Operation Instructions", and compare and confirm with the sample during the production process.
2. Confirm the paint test spray before production, and deal with the bad paint in time
3. During the production process, confirm whether the oil quantity and air pressure of the spray gun are within the standard range of the "Working Instructions"

Defective 9. Chromatic Aberration

Description:

Produces local or overall color differences on the surface of the coating. Generally, the overall color difference needs to take the standard sample as a reference, and the overall color is darker or lighter than the standard plate.

Analysis of the causes:

1. Improper spraying technique, a too thick or too thin topcoat

2. Too little or too much air pressure on the spray gun

3. Too little or too much fuel in the gun

4. The color difference of the paint itself

5. Color difference of electroplating coating

6. High humidity and moisture absorption

Key points of quality control:

1. In the production process, confirm whether the spraying times and the distance of the spray gun are consistent with the "Operation Instructions", and compare and confirm with the sample during the production process

2. During the production process, confirm whether the air pressure of the spray gun is consistent with the parameters of the "Operation Instructions"

3. During the production process, confirm whether the oil quantity of the spray gun is consistent with the parameters of the "Operation Instruction"

4. After the paint is toned, the color of the first piece is the same as the standard sample when confirmed

5. Confirm that the parameters of the electroplating furnace are consistent with the parameters of the "Operation Instructions"

6. Regularly confirm and record the temperature and humidity of the workshop (standard: relative humidity 65%±10)

Defective 10. Crack

Description:

Linear cracks on the UV primer or on the surface of the material are more obvious under the reflection of light or through light transmission. Cracks tend to worsen over time.

Analysis of the causes:

1. The UV energy is too strong

2. The UV primer is sprayed too thickly

3. Degreasing solvent is too strong

4. The UV primer is too strong, and the solvent penetrates into the material, causing cracking

5. The internal stress of the material is too large, and it is cracked by normal UV irradiation or solvent degreasing

Key points of quality control:

1. Confirm whether the number of strong and weak lamps in the UV furnace and the light energy are consistent with the "Operation Instructions"

2. In the production process, confirm whether the spraying times and the distance of the spray gun are consistent with the "Operation Instructions", and compare and confirm with the sample during the production process.

3. Before using different batches of flux, make a trial to confirm, and then put into production

4. Different batches of primer should be tried and confirmed before use, and then put into production

5. When the material is inspected, it will be confirmed as a trial production according to the standard process

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