Electronics Forum | Fri Aug 10 04:19:05 EDT 2001 | wister
There are lots of voids at solder joint of chips,the thickness of multilayer pcb is 3.2mm,top side have lots of chip component and bottom side has several BGA and QFPs.For top side profile,the preheat time is about 100s,soak time is about 75s,time ov
Electronics Forum | Mon Jan 15 18:24:40 EST 2007 | greg york
probably volatiles in the joint outgassing as it comes over the wave, is the joint a yellowy colour as well, or any pictures we can view cheers greg
Electronics Forum | Fri May 23 23:20:55 EDT 2003 | jedduan
What's the resistance value level of lead-free joint?Could anyone share me with the information? Thanks in advance Jed
Electronics Forum | Sun Sep 17 02:48:41 EDT 2006 | Eric
Anyone know any international standard (e.g. IPC, JIS) for the SAC lead free solder strength ? If no, any industrial / company standard for it ? Besides, any mathematical model which can help to calculate it.... express in "Force / area "
Electronics Forum | Mon Jan 15 08:01:14 EST 2007 | pyro747
The wave process, Flux (NR 330) 3 zones preheat top and bottom side convection, with solder pot at 260 C. PCB is ran in a selective wave pallet.
Electronics Forum | Tue Aug 14 17:55:01 EDT 2001 | Boysen
Are you using a water soluble paste? Older generations of water soluble paste are notorious for voiding. Some of the new generation water soluble fluxes allow a much wider process window.
Electronics Forum | Thu Nov 15 01:05:02 EST 2001 | jamstart
I think for x-ray, it really depend what package you are looking at. For CSP, it should be at least min 90KV, min 5 micro focus size. CSP definitely need a higher mag and resolution.
Electronics Forum | Wed Mar 30 16:07:24 EST 2005 | Dreamsniper
If there's no shear strength standard for solder joint, how will I define my pad width and length then. I have a 8.5 mils width and my component lead width is 8.66 mils based on manufacturer's minimum width specification. How will I identify that it
Electronics Forum | Sun Sep 17 09:02:53 EDT 2006 | davef
Just as you will not find such a specification for SnPb solder, you will not find such a standard for SAC. We talked about solder strength several times previously here on SMTnet. Search the fine Archives for others comments. For instance: http://
Electronics Forum | Tue Jan 16 11:24:47 EST 2007 | realchunks
I think John is right. I've seen the same thing (I think, without a picture who knows)on heavy heatsink parts. But I've also seen this happen on larger parts that move right after being wave soldered. I'm talking within a second or two of being so
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