Electronics Forum | Wed Jul 03 15:40:17 EDT 2013 | davef
Shear tests are [in my opinion] senseless. The shear stress you measure depends more on the shear rate and on the point where the force is applied than on the grain structure. When shearing a component, you not only apply shear stress, but also roll
Electronics Forum | Tue Aug 22 16:13:08 EDT 2000 | Dr. Ning-Cheng Lee
FR-4 will be OK for small products such as cellular phones. Here the temperature gradient across the board may be 3-4C only, and the board temperature can be well controlled. At temperature above around 245C, the discoloration and delamination may be
Electronics Forum | Tue Mar 29 14:45:12 EST 2005 | davef
IPC-TM-650 TEST METHODS MANUAL Number 2.4.21.1 Subject: Bond Strength, Surface Mount Lands Perpendicular Pull Method 1 Scope This test method is used to determine the bond strength (breakaway strength) of surface mount lands from substrate materials
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 30 21:07:35 EDT 2001 | davef
So, yer loosing parts between place and reflow? That would seem to say yer: * Paste has lost tackiness [check the fine SMTnet Archives for a sample test.]. * Really not placing the parts that you think yer placing. * Knocking the parts out of place
Electronics Forum | Tue Mar 22 07:39:05 EST 2005 | davef
There is no standard. This is a relative test. If you wish to do tests of this kind, we suggest to pay attention to the following points: * Shear strength of soft solder depends on the deformation speed applied. The faster the material is deformed t
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 May 10 16:49:14 EDT 2000 | Michael Parker
I would like informnation regarding this high heat withstanding type material for PCB, also any other types that are compatible. We currently use FR4 but have an application that may require most advanced composition.
Electronics Forum | Thu Aug 27 21:59:56 EDT 1998 | Xingsheng
Hi, Friends, Could you please recommend me some solder mask materials and equitements for high quality solder mask? Details such as company name, phone numer et al are welcomed. Thanks! Have a good day Xingsheng
Electronics Forum | Sat Aug 29 08:43:35 EDT 1998 | Dave F
| Hi, Friends, | Could you please recommend me some solder mask materials and equitements for high quality solder mask? Details such as company name, phone numer et al are welcomed. Thanks! | Have a good day | Xingsheng Xingsheng: Consider the follo
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