Cleaning Aluminum with White Marks after Ultrasonic Procedure

Q. During the ultrasonic cleaning procedure, white marks appear on our aluminium parts and they do not rub off. The only way to get rid of them is to use scotchbrite and rub them off. Any help would be very welcome.

A. There are a few steps that you may take to reduce this from happening.  First, when the aluminum parts are cut or worked they should be allowed to self passivate (sit in the air) for at least 30 minutes before cleaning.  Then they should be cleaned in the ultrasonic bath with our Citranox cleaner at a 2% concentration (2.5 oz. per gallon container). 

The temperature should be warm about 120 deg F or about 50 deg C.  There should be a couple of rinses.  The first rinse should be the same temperature and the last rinse may be room temperature.  The cleaner the source of water you use the better.  The final rinse should use the cleanest source of water available.  Then the parts should be dried off as quickly as possible.

For more information, please see the Citranox Technical Bulletin. To test an Alconox, Inc. detergent for free, please complete the questionnaire at Get Sample.