Electronics Forum | Thu Aug 24 16:59:11 EDT 2000 | Dr. Ning-Cheng Lee
For reflowed solder joints, Bi bearing solder has been reported to exhibit superior fatigue resistance. It also provides better wetting than many other alternatives, including SnAgCu systems. In my opinion, it may be the choice once all Pb can be pha
Electronics Forum | Wed Aug 23 16:46:52 EDT 2000 | Dr. Ning-Cheng Lee
Comparing 62Sn/36Pb/2Ag with 63Sn/37Pb, addition of 2% Ag introduces two major advantages. The first advantage is grain refining, and the resultant better fatigue resistance. The second advantage is a wider processing window on Ag metallization. Pres
Electronics Forum | Wed Aug 23 16:18:47 EDT 2000 | Dr. Ning-Cheng Lee
I presume you are referring to vibration test with fixed frequency at room temperature. One procedure describing the detailed profile is in MIL-STD-883E, Method 2005.2 (12/31/96). The approximate profile can be described as 60Hz, 20-70g, and 96 hrs t
Electronics Forum | Thu May 10 10:27:29 EDT 2001 | davef
It depends ... * Components stored in a garage in Chiriqui,Panama will have a different shelf life than those store in a climate controlled room in Ayrshire, Scotland. * Components from a reputable supplier will likely have a different shelf life tha
Electronics Forum | Mon May 14 09:24:36 EDT 2001 | rkevin
Can anyone shed some light on this for me ? Subject: Soldering to Immersion Tin surface finish I am looking for info. (pro and con) and/or 1st hand knowledge processing PCB's with Immersion Tin finish through SMT and Wave. Do profiles need to be di
Electronics Forum | Fri Jul 27 13:16:03 EDT 2001 | cjrjmj
I am looking at the Pump application for several bottom side applications we have. They are heavy in through hole radial and dip content. The initial testing of the stencil was very good, but I am concerned with inspection of the glue. We do a sampli
Electronics Forum | Thu Dec 30 23:25:49 EST 1999 | Henry C. Yao
We're using 96.5/3.5 high temp solder paste for our production and we're encountering soldering defects particularly non wetting (tombstoning). A technical document I read mentioned that there is a sort of a problem with the wettability of this paste
Electronics Forum | Tue Dec 14 12:00:34 EST 1999 | Kris Wiederhold
We recently reduced our standard aperture reduction to aid in the reduction of solder on gold defects. Since this reduction in aperture size, we have been experiencing exposed copper at the end of the component pads. The heel and toe joints are per
Electronics Forum | Tue Dec 14 20:57:07 EST 1999 | Curtis T.
John, I have never seen black pad covering a majority of the board, that would be a scarry thought. I think he is talking about building modules (sims dims) and getting soldering spatering on the gold edge connectors. We went the rounds with that s
Electronics Forum | Fri Nov 05 14:47:35 EST 1999 | Russ Cutler
We recently came to a cross roads... We have historically baked out ALL of our circuit cards, with a 2 fold purpose 1) to dry the part marking ink, and 2) to eliminate any moisture, which could result in measling further in the process of assembly.