Rust Free Cleaning of Component Leads & Boards

Q. Our current cleaning process has a tendency to leave spots on board and component leads. Analysis of the white spots shows oxides of tin and lead; rust-colored spots show iron oxide. FTIR analysis shows no organic content, so it’s not soap, flux, etc. I have recommended that the production people use appropriate Alconox, Inc. cleaner or possibly DI water only for a very short cleaning cycle, and that they dry the boards promptly in flowing warm air. Rust is coming from tinned steel component leads.

A. To clean component leads and boards with tinned steel component leads without forming rust:

• use a detergent with good chelating agents to control rust during cleaning and;
• be sure to rinse with ambient water;
• follow by water removing drying so that no rust forms during rinsing and drying.

We recommend using a 2% Citranox® Liquid Acid Cleaner and Detergent (20 g/L) to clean followed by a cool or ambient temperature rinse and blowing off the boards to remove the water with a minimum of evaporation.

To this or any request any Alconox, Inc. detergents for free, please complete the questionnaire at Get Sample.  For more information about any one of our Alconox, Inc. detergents, consult the technical bulletin for each product. Or click here to access each of our detergent’s  Safety Data Sheets.

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Contact us any time: cleaning@alconox.com