Hello,
I have a customer using a 95Pb/5Sn/2.5ag composition solder paste in a high temp copper lead frame application. The RMA flux is being cleaned but white residue around the solder points is noticed after the multiple rinse stages and dry (ultrasonic batch process).
Suspicion of having the rinse water too hot combined with the effects of high purity DI water causing corrosion to the lead solder.  Should the dryer be inerted?  Am I off base here?
 
Looking for advice from others using this type of solder formula .
 
Thanks

Charlie Pitarys
Director of Application Technologies
603.622.2900 X-115
www.kyzen.com