Electronics Forum | Wed Oct 06 03:18:01 EDT 2004 | Joseph
Dear all, Recently our customer complaint that some components being came off from the pcba after dropping test.But the curious is, the leads show visible solder fillet covering more than 75% of termination area on pad, which is acceptable as per IP
Electronics Forum | Wed Mar 30 16:46:03 EST 2005 | chunks
There is no spec because solder is designed to provide an electrical connection not a mechanical connection to hold the part on. If it where mechanical we�d be welding our parts on. Your pad width and length are derived from your component manufact
Electronics Forum | Wed Oct 06 22:55:14 EDT 2004 | davef
Your customer is correct. Components should not fall a board during a reasonable drop test. A shear test poorly represents a drop test. A drop test represents a drop test very well. If you want to proceed with shear testing, search the fine SMTne
Electronics Forum | Wed Dec 10 11:11:04 EST 1997 | Rich Scheleski
Is there a spec for the adhesives used to hold down parts before wave soldering. What size dots are recommended and what is the maximum shear force(1LB?) tested for to ensure good adhesion. Your help is appreciated Rich Scheleski
Electronics Forum | Sun Jan 11 12:03:51 EST 1998 | Bob Willis
As a basic guide the minimum spec you should look for is 500g you should achieve a force on most chip parts of 800-1000g. Parts are lost on wave soldering due to no material, poor curing, poor surface adhesion and poor handling. Its not the wave sold
Electronics Forum | Mon Jul 06 20:32:34 EDT 1998 | Chiakl
Hi there, I am looking for some informations concerning the shear or pull strength of a typical TQFP 20 mils leads in relationship with the Copper/Tin intermetalic layer thickness. Could anyone help? Thank in advandce. rgs, chiakl
Electronics Forum | Thu Jul 09 21:04:50 EDT 1998 | Dave F
| Hi there, | I am looking for some informations concerning the shear or pull strength of a typical TQFP 20 mils leads in relationship with the Copper/Tin intermetalic layer thickness. Could anyone help? | | Thank in advandce. | rgs, | chiakl Chiakl
Electronics Forum | Thu May 06 11:37:48 EDT 2010 | davef
There is no specification. Shear tests are very material / operator dependent. BALL SHEAR TESTING OF RAW BGA DEVICES: A total of 3 devices were subjected to ball shear testing. Results of the testing indicated shear values in the range of 0.7-1.25
Electronics Forum | Fri Aug 08 11:44:44 EDT 2003 | Henry
I am fairly new to wave soldering and production processes, but I have been tasked with coming up with a calculation involving the shear strength of some through-hole leads. The leads are tinned copper and I suspect that tinning reduces the shear st
Electronics Forum | Wed Oct 05 15:03:40 EDT 2005 | Amol
depends on what you want evaluated! you can thermal cycle the BGAs and the examine the x-sections to determine failure modes at different stages of thermal cycles. you can do a stress test and corelate the # of thermal cycles with the microstructu
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