February 8, 2009

Chemical Composition For Cleaning

The detail of chemical composition and conditions of use of cleaning materials for aluminum, copper, copper plate, iron, steel, magnesium, and zinc by various methods of application are discussed by Myers and Spencer.

Typical cleaner formulas were given in the table before. Typical operation conditions are given on the table below. Proprietary metal cleaner are developed for specific metal cleaning applications and include vendor technical service. This service can be a big asset to the user.

The controlling factors in cleaning are the concentration of the cleaner, the temperature of the solution, the time of the cleaning action, and the applied energy. Each can be varied to obtain maximum results. The concentration should be in the recommended range. The time must be sufficient to do the job. The temperature should be adjusted for maximum cleaning efficiency, but must not be too high or dry down residues will cause plating problems. The applied energy in the form of agitation, circulation, hydraulic spray action, electric current, or ultrasonic pulsation will be helpful only if the cleaner is right for the job at band. A spray cleaner is not a good soak cleaner or a good electrocleaner. A soak cleaner will foam too much to be used for spray cleaning or electrocleaning.


Metal Being

Cleaned

Cleaner Cons.

g/l

Dirrect Current, A/dm2

Temperature

oC

Steel

60-120

5-10

82 to boiling

Copper

30-60

2-5

71-82

Brass

25-45

1.5-5

60-82

Zinc die casting

30-45

2-5

66-77

Lead

30-45

1.5-5

60-71

Aluminum

30-60

None

71-82

Good solution control by chemical titration or automatic controls and a complete running record of the concentrations and the additions are recommended for all cleaning operations. This information is necessary for establishing costs and is useful in determining dumping cycles. A good maintenance program with good records is a big asset in preventing plating shop emergency problems. Many hours are lost and rejects pile up when cleaning solutions are not maintained. Poor cleaning leads to poor plating. Good cleaning and rinsing are necessary for quality electroplating.


Post by Aluminum Anodizing.

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