Gold Immersion Solder Joints

What should a good gold joint look like? We've run boards for our customers that look kinda dull but seemed to wet properly and the boards fired up just nicely! Should they look nice and shiny like our HASL boards or is "a shiny joint is a good joint" just a myth?

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| What should a good gold joint look like? We've run boards for our customers that look kinda dull but seemed to wet properly and the boards fired up just nicely! Should they look nice and shiny like our HASL boards or is "a shiny joint is a good joint" just a myth? "Shiny is good" is a myth. Expect duller joints with Immersion Gold. Still look for nicely wetted concave fillets.

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| | What should a good gold joint look like? We've run boards for our customers that look kinda dull but seemed to wet properly and the boards fired up just nicely! Should they look nice and shiny like our HASL boards or is "a shiny joint is a good joint" just a myth? | "Shiny is good" is a myth. Expect duller joints with Immersion Gold. Still look for nicely wetted concave fillets.

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| What should a good gold joint look like? We've run boards for our customers that look kinda dull but seemed to wet properly and the boards fired up just nicely! Should they look nice and shiny like our HASL boards or is "a shiny joint is a good joint" just a myth? Bruce, Welcome to America. Though, you've probably been here all your life. Shiny joints are "Americanisms." There is no data supporting a shiny joint being any more reliable than a dull joint if the profiles are correct and the solder joint has properly formed. If you go to Asia and you look at boards over there, the joints are frequently dull due to materials and process differences. that's because they're not concerned with the aesthetics of the PWB's solder joints. They are concerned with the true goal, functionality. That may be a gross generalization and I apolagize to any Asian fabricators whom are concerned with the brightness of solder joints but reliability IS your main concern and I commend you for that as "that's the way it should be." You're joints are dull because of the gold flash. Jump your reflow temperature up another 10 to 20 degrees C and you'll see your bright solder joints. Jumping up the temperature allows the gold to effectively "dissolve" into the tin/lead, thus producing a shiny joint. Regards Justin Medernach

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Yes bright shiny joints are a myth as many people like dull joints as they are easier to inspect due to reduced reflection of light. The difference you are seeing in the joints is more likly to be a surface effect, flux or just you think its different as the gold is a new finish. Further information on alternative solder finishes, cost and benifits are on my download section of my web site. www.bobwillis.co.uk | What should a good gold joint look like? We've run boards for our customers that look kinda dull but seemed to wet properly and the boards fired up just nicely! Should they look nice and shiny like our HASL boards or is "a shiny joint is a good joint" just a myth?

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