Electronics Forum | Fri Apr 16 08:20:58 EDT 2004 | Bob L.
We've seen problems with BGA balls breaking at in-circuit test. I did some bend testing and found that our large BGA's can handle amazing stresses at low strain rates but we get brittle fractures at high strain rates, especially with Ni/Au surface f
Electronics Forum | Thu Nov 03 08:18:17 EST 2005 | fctassembly
Hello Arnold, Just to clarify the Sn100C discussion: Please note that SN100C is the Nihon Superior alloy composed of tin/.7copper/nickel. The key point in regard to SN100C is that Cu does not go directly into solution but first reacts to form an inte
Electronics Forum | Tue Jan 30 01:06:51 EST 2018 | dgassier81
Hi, In our shop we've always baked out PCBs and moisture sensitive parts prior to electronic assembly using a gentle ramp rate of 2 degC/minutes going hot (93degC) and same ramp rate going cold (back to room temp). We're trying to outsource that pro
Electronics Forum | Thu Aug 26 13:20:56 EDT 2004 | pjc
Machine design plays a major factor in actual placement rate vs. the published tact time max speed. For example, random access horizontal turret head machines can vary greatly depending on nr. of different components and size ranges, while the dual g
Electronics Forum | Thu Jun 14 21:06:49 EDT 2001 | davef
We rate each board for producibility. [Our rating chart may be based on some things that Bob Willis did. Check his site [http://www.bobwillis.co.uk/ ] for all kinds of neat stuff. Maybe even bring him in to help you sort through things.] There
Electronics Forum | Tue Oct 06 08:20:13 EDT 1998 | Charles Stringer
| Does sombbody know what DPM rate a good and reliable SMT assembly line (incl. solder paste print, assembly and feflow soldering) has? | DPM is Defects per million, usually measured on components. We run a process consisting of small to medium batch
Electronics Forum | Tue Apr 09 00:09:25 EDT 2002 | craigj
Question. When profiling and looking at the profiles cooling rate. Over what temperature range should the slope be monitored and what sort of cooling rates should be looked for. Paste supplier says no more than 6degC per sec, some components maybe lo
Electronics Forum | Mon Jun 20 21:54:38 EDT 2005 | darby
Contact your paste supplier and see what they say. My information on SAC 305 FROM MY SUPPLIER was - "The cool down rate is not as critical for Pb-free solder joints, as it was for SnPb. The grain sizes do not differ is size in the Pb-free bulk solde
Electronics Forum | Wed Jan 03 09:59:52 EST 2007 | Jim
Hi, I was looking for information on failure rates for BGA components. I am analyzing our BGA rework rates and find it difficult to define a root cause when a remove and replace of the BGA component corrects the test errors. Inspection prior to re
Electronics Forum | Fri Feb 16 13:43:07 EST 2007 | ck_the_flip
Hi Darby, Where did you get the info. that cooling rate is not-as-critical for lead-free? I'm not doubting you, and I actually want this to be the case. We don't have chillers on our ovens, and on fast profiles, we only achieve 2 to 2.5 deg. / s c
