Electronics Forum | Mon Apr 25 22:56:44 EDT 2005 | davef
rush316 First, no one stated that PBB and/or PCBE are in FR4. FR4 contain tetra-bromo-bisphenol A [TBBA]. Second, there are classes [and grades] of dielectric materials used in fabricating printed circuit boards. Grades, NEMA LI-1. From these gr
Electronics Forum | Mon Apr 25 17:07:11 EDT 2005 | rush316
You indicate that PBBs and PBDEs are included in FR4 materials!! Does this include PCB (Printed Circuit Boards)??
Electronics Forum | Thu Jun 24 23:57:42 EDT 2004 | George
Could anyone tell me the difference in PCB material Nelco13 and FR4? PCB dielectric material Nelco13 is quite new for me and I knew nothing about it. For imcoming quality control (IQC), I am asked to identify PCB made of FR4 and Nelco13. How to do th
Electronics Forum | Tue Jul 11 10:13:22 EDT 2006 | SWAG
Over time, you might see problems with delam., blistering and warpage if using FR4 carriers. Depending on volumes, you might consider using durostone or some robust material like that for the production runs. Keep in mind that switching materials w
Electronics Forum | Mon Jun 28 01:44:02 EDT 2004 | George
Thanks a lot !
Electronics Forum | Fri Mar 11 18:47:54 EST 2005 | davef
JD: It's important to note that FR-4 does not contain PBB or PBDE. The bromine in FR-4 epoxy comes in the form of tetra-bromo-bisphenol A [TBBA], which polymerizes and become part of the cross-linked epoxy. Bromine, in the form of hydrogen bromide, i
Electronics Forum | Fri Jul 28 14:34:13 EDT 2000 | Gary Simbulan
Belive it or not, these boards were run through a Centech batch mode Vapor Phase machine. Single stage top side IR preheat. Vapor temp 218 C. Solder paste is an SN62 RMA.The boards were FR4 8 layer w/ solder mask, fairly conventional as might be e
Electronics Forum | Tue Aug 28 11:12:23 EDT 2007 | grics
This is what I was thinking, but I am being beat up pretty badly by the selective solder. Ambient temperature is anywhere in the the neighborhood of 76 - 80 degrees F. I am not sure of the RH, but I wouldn't think that would be my issue... One of
Electronics Forum | Fri Jun 25 07:13:40 EDT 2004 | davef
Nelco was developed by Park [ http://www.parknelco.com/parknelco/highspeed.htm ] Without fairly involved testing, you may be forced to rely on a c of c from your fabricator. Although, Park may be able to give you a lead.
Electronics Forum | Tue Jun 13 08:33:11 EDT 2006 | davef
IPC-2222, 5.3.1 defines the parameters of making scoring cuts and the tolerance of the cuts, but does not specify the cuts. Our spec for 0.062" thick FR-4 boards is: 0.018-0.024"
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