Subject: | |
From: | |
Reply To: | TechNet E-Mail Forum. |
Date: | Wed, 22 Apr 1998 00:51:49 EDT |
Content-Type: | text/plain |
Parts/Attachments: |
|
|
Hi Phil,
That German study was indeed on chip components.
I have not seen, or even heard of, this AMP study, so you have me at a
disadvantage.
Butt-joints are a real problem in any case, that is why they have all but
disappeared. But there is no reason why an off-center (within reason, of
course) gull-wing solder joints should be any less reliable, at least for
thermal cycling. Now, there have been studies, where strenght has been equated
with reliability—off-center solder joints are likely somewhat less strong than
perfectly cetered ones, but any properly wetted solder joint has more than
ample strenght to survive all but deliberate shear- or pull-off tests. But
solder joint strength can not be equated with reliability for thermal cyclic
fatigue.
If you have a copy of this AMP report I would like one, otherwise, p[erhaps
you recall the definition of reliability in this study.
Werner Engelmaier
Engelmaier Associates, L.C.
Electronic Packaging, Interconnection and Reliability Consulting
7 Jasmine Run
Ormond Beach, FL 32174 USA
Phone: 904-437-8747, Fax: 904-437-8737
E-mail: [log in to unmask]
################################################################
TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c
################################################################
To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body:
To subscribe: SUBSCRIBE TechNet <your full name>
To unsubscribe: SIGNOFF TechNet
################################################################
Please visit IPC web site (http://jefry.ipc.org/forum.htm) for additional information.
For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311
################################################################
|
|
|