Soldering Iron Tip Corrosion

[BuffaloEngineer]

We've been using lead free solder for a while, and I've noticed we keep corroding our solder tips after a week or three of use. We've used rosin core and no clean SAC305, both seem about the same in terms of corrosion. Tried the "tip activator" from Weller, basically retins the tip, but that's not effective once the tip is corrded.

Does anyone else have these issues? I just switched back to Tin/Lead so I don't get slowed down by tip corrosion as much... Thanks!

 

[KeepItSimpleStupid]

Eat your heart out: https://www.google.com/url?sa=t&rct...DsEGgRyGPDShFow&bvm=bv.74649129,d.cWc&cad=rja

 

[jbeng]

Not sure what is really going on there, but one problem you might be experiencing is the effect of tin dissolving the copper of your soldering tips.
Tin, when in a liquid state, readily dissolves other metals such as copper, silver and gold. Tips are usually coated with a layer of iron for durability, but if that iron layer gets breached (eg. cracked or ground / scratched through) it is only a short time before the copper begins to dissolve into liquid-solder solution. Damaging the iron layer is a major reason a lot of people caution against grinding or filing your solder tips to reshape them. Since SAC305 solder is 95% tin (and the working temperatures are higher), it will dissolve copper far faster than standard 63/37 SnPb. I've seen it happen on component leads many times.
Google "dissolution of copper in lead free solder alloys"

 

[Ian Rogers]

I have found that when I try to use lead free solder I need to bump the temp settings up a little... If I use my iron between 320 - 350°C the tips last absolute ages... When I have it closer to 380°C the tips corrode for fun.... At £6.80 a pop, it becomes a bit expensive... I switched back to lead solder and run my iron at 325°C all the time...

 

[crutschow]

There are solders have a small amount of copper added to reduce the erosion of copper tips, for example here.

 

[chemelec]

I use Kester 331 Solder that is Tin/Lead, with a water based Flux in it.
Just Warm water to remove the Flux from the boards.
I use my Soldering Iron Everyday and the tip is Still good now, and over 5 Years of use.