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gold embrittlement on paste in hole 30 micro in. gold plated lead

#11305

gold embrittlement on paste in hole 30 micro in. gold plated lead | 28 May, 1999

I discovered that we have some gold plated (30 mico in.) through hole connectors which were Paste In Hole soldered (60 sec at reflow) on a HASL PCB. Do we have an embrittlement reliability issue? The calculated volume % of gold in the joints is about 0.5%. Does the gold completely disolved in the solder? The product may be in use for up to 10 years. (I'm tinning now)

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Glenn Robertson

#11306

Re: gold embrittlement on paste in hole 30 micro in. gold plated lead | 28 May, 1999

| I discovered that we have some gold plated (30 mico in.) through hole connectors which were Paste In Hole soldered (60 sec at reflow) on a HASL PCB. Do we have an embrittlement reliability issue? The calculated volume % of gold in the joints is about 0.5%. Does the gold completely disolved in the solder? The product may be in use for up to 10 years. (I'm tinning now) | Dave - I think you should be OK. 30 micro" Au will dissolve in solder in less than a second, so there should be time for the alloy composition to homogenize. You might want to checkj a reference such as Jenny Hwang's book (Modern Solder Technology for Competitive Electronics Manufacturing), page 407-413. Also, you may need to trim the leads if you leave them un-tinned. Some of the solder may want to stay on the tips of the leads, rather than moving up into the barrel.

Glenn Robertson glenn.robertson@usa.alcatel.com

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