Electronics Forum | Mon Feb 27 09:09:36 EST 2006 | davef
Silver on your copper or brass part is a solderability protection. The silver diffuses into the solder and you solder to the base metal, either the copper or brass in your case. Soldering to copper is well known. The issues are soldering to brass
Electronics Forum | Tue Mar 20 20:12:32 EST 2001 | davef
In response to a similar question Dennis Fritz [DDFRITZ@AOL.COM] Chair of the Alternate Final Finishes Committee of IPC (5-23d) said ... The Alternate Final Finishes Committee of IPC (5-23d) has nearly completed a round robin "conditioning" study of
Electronics Forum | Fri Feb 01 08:35:18 EST 2002 | gregers
PWB shelf life: HASL---3mth ENTEK-- 2mth Before using expired PWB, it is suggested to go thru HASL or ENTEK angain. Ask your VDR to serve this. Re immersion Au, mostly when the thickness under 3u"(micro pores present), the surface gold will serve a
Electronics Forum | Wed Jul 15 17:36:26 EDT 2015 | mikekeens
From my experience Electroless Nickel Immersion Gold or ENIG finish gives the best results but does cost more than other available finishes. It has good solderabilty, good shelf life and is flat. Details of other available PCB surface finishes can
Electronics Forum | Fri Feb 02 12:37:16 EST 2007 | Derek W
We've had the same issues with silver. We also ran into shelf life issues but that's specific to our business. We've moved to ENIG with good success, our board vendors were also very happy to move away from silver though I'm not sure why. As long as
Electronics Forum | Tue Sep 11 22:52:18 EDT 2007 | davef
Here are some options for removing OSP coatings from pads of the BGA substrates. * Leave the substrates in storage for 13-14 months. Shelf life of OSP coating is ~12 months, depending on the product. * Wash the substrates in your aqueous washer. Ea
Electronics Forum | Tue Jan 04 15:38:19 EST 2000 | Pat Pepper
Hi everyone: Our company is trying out immersion white tin for fine pitch assembly with what I would call mixed results. Reflow solder looks very good, but wave solder looks somewhat grainy (this may not be a problem in actuality). We had dewettin
Electronics Forum | Thu Sep 16 01:54:46 EDT 2010 | sachu_70
Hi Gani, Immersion Ag finish has lesser shelf life as it can get more easily oxidized on exposure. However, I see concern in your Reflow profile. A few questions: Have you compared your reflow profile to the solder paste manufacturer's recommended pr
Electronics Forum | Tue Feb 01 21:51:05 EST 2000 | Dave F
Roni: Ron gives good advice on the thickness of your Electroless Nickel - Immersion Gold (ENIG) solderability preservative. Several additional comments are ENIG: � More expensive than OSPs and HASL. � Much flatter surface than HASL, similar to OSP
Electronics Forum | Wed Sep 01 08:27:38 EDT 2004 | davef
Zinc from the brass [Cu3Zn2] diffuses into the tin causing solderability problems. Just 0.001% of Zn in your solder can render it fit for the scrap heap. So, you need a barrier plate between the brass and the tin. Copper or nickel-plating is commonl
