Electronics Forum | Mon May 20 10:49:12 EDT 2002 | geoff_goring
Are we saying then that IMC can occur at the solder / Cu pad join on the PCB when finished assembled? In our case we are being told that this process is starting before assembly. Is it fundamentally the same thing. i.e. will the Tin diffuse with th
Electronics Forum | Tue May 28 09:27:04 EDT 2002 | pjc
Does this PBGA have eutectic balls? If so and the PCB is HASL finish, or has solder on the lands from BGA removal, you may not have to apply solderpaste. Check with you flux supplier to see if they offer a NC "flux paste" product, otherwise I know Mu
Electronics Forum | Tue Jul 16 10:15:12 EDT 2002 | robbied
Hi, we have recently had some customer returns where the 44 pin j-lead ASIC devices exhibit green corrosion from the copper under the tin plating on the leads. These boards were in the field for around 4 years, with innadequate conformal coating pro
Electronics Forum | Tue Jul 16 21:28:41 EDT 2002 | davef
Questions are: * What is this green material? * What does the green material look like? * What the impact of this material on the long-term reliability of your customer�s product? * What flux did you use to solder these boards? * How were the boards
Electronics Forum | Mon Mar 31 11:10:43 EST 2003 | davef
First, most �thermal shock� recipes are not a reliability test. There is no relationship between the failures seem in these tests and in-use application. These tests show you the failures in these tests. That�s it!!! Second, accelerated life test
Electronics Forum | Thu Apr 15 11:14:34 EDT 2004 | mikecollier
Our conformal coat area has recently requested changes to our bare board houses to perform a pumice scrub operation on the PWB prior to HASL plating and delivery to us. Our first lot received caused us to have void faults under multiple component ty
Electronics Forum | Fri Apr 22 10:12:14 EDT 2005 | davef
Common RTV does out-gas causing corrosion. NASA allows use of non/low-out-gassing RTV. Try the following companies: * Ablestik Electronic: Materials, 20021 Susana Road, Rancho Dominguez, California 90221 U.S.A., 310-764.4600, F 310-764-2545 * Arlon
Electronics Forum | Wed Apr 26 07:37:34 EDT 2006 | amol_kane
"Can we reuse the same machine? My point here is that the non lead free process has already coated the machine interior ( exhaust, internal flow ) with leaded component, and by conversion to lead free are we containminating the lead free product from
Electronics Forum | Wed Apr 26 07:37:52 EDT 2006 | amol_kane
"Can we reuse the same machine? My point here is that the non lead free process has already coated the machine interior ( exhaust, internal flow ) with leaded component, and by conversion to lead free are we containminating the lead free product from
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
