Printed Circuit Board Assembly & PCB Design SMT Electronics Assembly Manufacturing Forum

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.


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#72278

| 17 June, 2014

#72293

| 20 June, 2014

Your pot has a yellow tint? Have you had it tested recently?

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#72294

Lead-Free wave solder has yellow hue/tint | 22 June, 2014

I don't know. We never had craziness like this before lead-free.

You should have the yellowish-metal analyzed to be sure.

Guessing: You're seeing this color on the terminations of components, not on the bulk of the SnX solder connection. If that's the case, here's what's going on, probably: * Bulk solder and component termination are blistering hot * High soldering temperature has melted the metal solderability protection on the component termination * Surface tension of the bulk solder has pulled the component termination solderability protection into the bulk solder, leaving behind the exposed stainless steel or nickel barrier * Thin nickel oxide films form on the component terminations that change color according to temperature or exposure time during soldering

BR ... davef

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#72398

Lead-Free wave solder has yellow hue/tint | 10 July, 2014

I'm not sure what happened to my post, but we think to have got the situation under control. The solder joints on the boards looked terrible. I can only describe it as unburnt flux, maybe. (like if you took a spoonful of solder and sprayed flux directly onto the solder puddle) We think there may have been a contaminate (perhaps a tool or it's handle) stuck or melting down in the channels of the solder pot.

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