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Another PbF indicator?
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N_Cook
Jan 24, 2011, 6:06:58 AM1/24/11
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On a recent "American" board , made in China, so no warning legends of PbF .
Don't know what its called, the sort of conformal coating final process at
the pcb production phase is a staining coat , usually green these days.
White rings showing around the solder pads after soldering may show elevated
soldering temperature has been used or wrong composite material body ,
showing rings of plain white polyester+fibre board . The green staining
having melded into the plastic or evaporated.
Don't know what its called, the sort of conformal coating final process at
the pcb production phase is a staining coat , usually green these days.
White rings showing around the solder pads after soldering may show elevated
soldering temperature has been used or wrong composite material body ,
showing rings of plain white polyester+fibre board . The green staining
having melded into the plastic or evaporated.
From UL 6 digit E number and board type this is designated 260 deg C / 10
second solder dwell ( for conventional soldering) rather than 270 deg / 10
second dwell of proper made for PbF pcb boards.
N_Cook
Jan 25, 2011, 9:32:25 AM1/25/11
to
If anyone knows the significance of 288 degree C / 8 second soldering dwell
time pcb +soldering rating in comparison to 260/10 and 270/10, I would be
interested to hear.
time pcb +soldering rating in comparison to 260/10 and 270/10, I would be
interested to hear.
N_Cook
Jan 26, 2011, 4:01:08 AM1/26/11
to
IPC-TM-650 Test Method 2.4.24.1. would seem to be the test, should anyone be
interested
Time to Delamination (TMA Method)
10 second solder float
http://www.matrixusa.us/pdfs/solutions/Lead-Free_Basics.pdf
http://www.ipc.org/4.0_Knowledge/4.1_Standards/test/2.4.24.1.pdf
interested
Time to Delamination (TMA Method)
10 second solder float
http://www.matrixusa.us/pdfs/solutions/Lead-Free_Basics.pdf
http://www.ipc.org/4.0_Knowledge/4.1_Standards/test/2.4.24.1.pdf
N_Cook
Jan 26, 2011, 10:24:37 AM1/26/11
to
Wrong tests , more likely this test, as seconds not minutes, peel strength
not delamination
not delamination
Solder float peel strength: (no change after 288C/10 sec)
eg
http://www3.uic.com/wcms/images2.nsf/(GraphicLib)/2006_PCB_Damage_Test_Plan.
pdf/$File/2006_PCB_Damage_Test_Plan.pdf
N_Cook
Jan 27, 2011, 3:16:04 AM1/27/11
to
So I reckon the ul.com pcb classification is this test
http://www.ipc.org/4.0_Knowledge/4.1_Standards/test/2.4.8.3a.pdf
with 10 second solder float for the heating stage
Then passing 260 degree C for leaded solder use
270 deg C for PbF
288 deg C for high spec like polyimide/ N7000-1 /Pyralux
http://www.ipc.org/4.0_Knowledge/4.1_Standards/test/2.4.8.3a.pdf
with 10 second solder float for the heating stage
Then passing 260 degree C for leaded solder use
270 deg C for PbF
288 deg C for high spec like polyimide/ N7000-1 /Pyralux
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