Electronics Forum | Fri Apr 30 10:50:24 EDT 2010 | dldavis
Where do I find data which shows how much dwell time is excessive in a solder fountain when install through hole connectors into a polyimide board.
Electronics Forum | Mon May 03 10:52:18 EDT 2010 | davef
We're not sure that such data is available. What guidelines does your flux supplier provide in soldering with this process?
Electronics Forum | Mon May 03 11:20:43 EDT 2010 | mikesewell
A good guideline is keep it similar to your wave solder process, for example 2-3 sec. This assumes you're preheating the assembly. While polyimide boards are fairly robust at some point you will begin to see copper dissolution - the solder side pad
Electronics Forum | Thu Jul 29 00:42:32 EDT 2004 | C.W
hello, BGA was a little excessively reflowed with dwell time(above 183C - solder paste = 63/37) over 2 min, peak temp is 218C. I inspected the BGA under X-ray and there is a little voids but within the acceptable range, i then used the Ersascope to c
Electronics Forum | Fri Jul 30 09:59:10 EDT 2004 | Steve
Excessive Time above Liquidus will cause a solder joint to become extremely brittle. Any shock or stress to the joint can lead to a failure.
Electronics Forum | Wed Aug 04 15:27:03 EDT 2004 | Rush Fan
I might suggest that you check with your solder paste manufacturer to see what is recommended for time over reflow. Typically, I think most are between 60 and 90 seconds over 183. Also, consider the rate of cooling. The faster you cool the solder, th
Electronics Forum | Tue Dec 14 10:58:56 EST 2004 | Peppe
Thanks for your answer Dave. Just a clarification. Given FIT is for just one soldering or for a specific number ? I mean cards we produce have, typically, 10000 soldering joints. Which is the expected FIT of that card ? Thanks again for your help.
Electronics Forum | Mon Dec 13 06:21:14 EST 2004 | Peppe
I work in electronic industry and I'm interested about the standard values of FIT (failure in time or useful lifetime) of soldering. In essenze my question is : how much time can work a good solder joint, before became fail ? Exist a minimum and ma
Electronics Forum | Tue Dec 14 20:31:53 EST 2004 | davef
The FIT we mentioned is for a stocked, finished good item. It's for something shipped to a customer.
Electronics Forum | Tue Dec 14 08:32:10 EST 2004 | davef
Depending on the design, materials selection, end use, etc; we'd expect the FIT of an electronic assembly to be between 30 and 100+. There is no standard.
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