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grey appearance on solder joints after batch cleaning

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#71707

grey appearance on solder joints after batch cleaning | 11 February, 2014

Process: Batch Cleaner, @16% concentration. Concentration is checked daily. Cleaning after Wave Process.

See attached pictures and comment and what you think causes the solder joint to turn grey. i have read post that say the grey dull looking solder joints are process indicators. are there any white papers that support this as non issue. thanks, JC

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#71711

grey appearance on solder joints after batch cleaning | 11 February, 2014

I can't speak too much as to why your joints are appearing dull, even with the booster. I can recommend a new chemistry that Kyzen has out that I've been running for about a year now. Price is about the same, it can be run at low(er) concentrations, and it doesn't require any additives (boosters).

http://www.kyzen.com/Aquanox/A4639.html

I know it doesn't address the immediate concern, but maybe it'll help down the road.

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#71826

grey appearance on solder joints after batch cleaning | 12 March, 2014

The grey solder joint appearance in the picture looks to be due to chemistry etching the joints. This can be a common problem with alkaline chemistries running at high concentrations and or alkaline chemistries running in batch machines that require wash cycles that exceed 15 mins. I would recommend a pH neutral aqueous based chemistry or one with a good inhibitor built in to the formulation.

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