Electronics Forum | Fri Sep 17 03:03:29 EDT 2010 | grahamcooper22
Hi Gani, looking at the HASL icture and the poor wetting of the solder over the pads I would imagine that the HASL coating is very thin on the pads and in actual fact isn't 'solder' but is tin /copper intemetallic and this has poor solderability. It
Electronics Forum | Tue Sep 14 14:07:45 EDT 2010 | grahamcooper22
Hi Gani, HASL is normally very good for solderability providing there is a good consistent coating of HASL on the pcb pad. But it is not unusual to have a very thin coating of HASL on the pad and this is poor for solderability. You then have tin/copp
Electronics Forum | Wed Mar 11 10:58:58 EST 1998 | Earl Moon
| | What does the term "poor wetting" mean as a defect code ? "Poor" should mean unacceptable when surface (component or PCB solder termination areas) wetting does not provide acceptable solder joints. Unacceptable wetting of PCB solder termination
Electronics Forum | Wed Jul 29 13:44:45 EDT 1998 | David Spilker
We are investigating alternatives to HASL finishes for more dense PWBs. OSP is not a good choice because of low solid flux and possibly long shelf life. Immersion gold is expensive and so far has been more difficult to wave solder. Has anyone had
Electronics Forum | Mon Aug 07 09:04:09 EDT 2006 | molos21
Hi everyone, I am starting to use the lead free process and I had a few wetting problems (solder did not reach top side) at the wave soldering process once the pcb had passed our smt line (one heat pass). From what I understand, I have had a problem
Electronics Forum | Wed Feb 08 04:08:35 EST 2006 | fctassembly
Hello Greg, I agree with you that the article in SMT Magazine should be studied very carefully as it contains many errors in respect to SN100C. The testing performed was a DOE and was not an optimized run. There is also a statement on dross generatio
Electronics Forum | Thu Dec 17 03:45:47 EST 2009 | tod1967
was the wetting test conducted with SN96? Do any Pull or stress testing?
Electronics Forum | Mon Feb 06 13:00:51 EST 2006 | amol_kane
Hi all, I just wave soldered 40 boards (20 if Imm Sn and 20 of Imm Ag) using SAC 305 (in this case the wave machine manufacturer (electrovert) suggested the alloy too). plan to carry out x-sectioning to see the results. overall, just from the visual
Electronics Forum | Sun Feb 05 08:41:15 EST 2006 | Cmiller
Are you refering to reflow soldering or wave soldering? Brian, do you have any data to support that SAC305 is more reliable than Tin-Copper-Nickel? NEMI reccomended SAC type alloys for reflow and Tin-Copper for wave. See: http://circuitsassembly.
Electronics Forum | Tue Feb 07 13:39:42 EST 2006 | gregoryyork
You can use straight forward Tin/Copper but it flows very poorly so solderability is an issue. Dosing with Phos improves this but need to stay on top of it. We have supplied some 3.8%Ag alloys for flow they work well but you get a small 'chill point'
.gif)
winsouce.jpg)