Electronics Forum | Wed Aug 09 08:06:07 EDT 2006 | davef
See "IPC-4554 Specification for Immersion Tin Plating for Printed Circuit Boards" 3.2.1 Immersion Tin Thickness. The most common reason for solderability issues with the white tin surface coating during multiple thermal excursions is a thin white ti
Electronics Forum | Wed Aug 30 08:20:40 EDT 2006 | Bob R.
Are there any standard qualification/acceptance requirements for immersion tin board finish? J-STD-003 calls out temp/humidity preconditioning followed by solderability testing which is similar to what we have in our (ancient) internal documents. O
Electronics Forum | Fri Dec 16 08:00:26 EST 2005 | jax
What you are most likely dealing with: Insufficient Pure Sn layer ( multiple causes ) Because elevated temperatures accelerate the diffusion process, the thickness of the Pure Sn layer will reduce during every thermal cycle... ( bakeing PCBs, S
Electronics Forum | Fri Dec 16 08:16:41 EST 2005 | davef
Heat cycles deplete the pure tin layer. Each solder cycle reduces the tin thickness by ~0.1 micron (4 uin). So, if you start with a thin imm tin coating you'll have problems after multiple heat cycles. Steve Wentz says, "In almost every case I've
Electronics Forum | Mon Dec 12 15:57:58 EST 2005 | Samir Nagaheenanajar
4% of the alloy), there is a ternerary phase (not sure if i spelled that right) where the melting point of the alloy is MUCH less than, say, SAC305's. Sn-Bi has also been associated with...... none other than Tin Whiskers. There are some in the in
Electronics Forum | Tue Dec 13 14:55:12 EST 2005 | muse95
Your response is from the point of view of using a Bismuth solder with Pb plated leads. Samir's point of view is from Bismuth in the plating on the leads being used with a Pb solder. There is a very large difference in the amount of Bi that will en
Electronics Forum | Tue Feb 01 09:54:23 EST 2005 | jbrower
Hi Frank, we're still going to go with FR4 as our prefered material. Our board thickness is .062. We use an on shore and off shore vendor. Prototron I believe offers an immersion tin and excellence in china? offers an immersion tin finish. We fou
Electronics Forum | Sat Jul 28 08:37:52 EDT 2007 | davef
There is no good choice. Board Finishes: Industrial/Battelle Class 3 Environment [Reliability Knowledge Gaps: For use of Pb-free solders in High Reliability Applications, J Smetana, iNEMI Availability of SnPb-Compatible BGAs Workshop, March 1, 2007,
Electronics Forum | Thu Aug 03 10:53:23 EDT 2000 | Roni Haviv
Hello, Does enyone have any experience with Immersion Tin (Sn) as a finish process on PCB ? Any information will help ! Thanks Roni
Electronics Forum | Tue Oct 25 18:58:40 EDT 2005 | davef
Could you be talking about immersion tin?