Electronics Forum | Mon Nov 13 18:36:32 EST 2023 | emeto
Your reflow profile should be designed towards the flux in your solder paste. To form a proper inter-metallic layer, you need to reach 20-30C above your melting point and stay in liquidus state for certain amount of time. SAC 105 has 3C difference fr
Electronics Forum | Wed Aug 19 18:18:02 EDT 2009 | smt_guy
Thanks Sir Dave. Yeah my apologies. To clarify, we built the product PCB whcih has a Lead-Free HASL Finish using a Sn63/Pb37 Solder paste. My major concern regarding reliability is that my profile whish is between 215'C-225'C was insufficient to ref
Electronics Forum | Thu Mar 28 14:04:16 EST 2002 | davef
Intermetalic Layer (IL). A compound formed at the interface of two different metals, whose atoms have an extremely high natural attraction for each other, so high, that they do not bond to other elements by any other means. Also, intermetalic compo
Electronics Forum | Wed Sep 10 12:56:09 EDT 2003 | davef
Intermetallic compounds [IMC]: * Form during the alloying process of some metals. In soldering these are Sn, Ni, Ag, Cu, Au. * Do not accept solder. * Increase in depth in logarithmic proportion to both time and temperature. [So during the solder
Electronics Forum | Thu Sep 07 08:50:45 EDT 2006 | Grant
Hi, We have seen a slight rise in failures in a product, and on investigation, the BGA ball has cracked off the PCB. It's below the intermetalic layer in the ball. Reflow otherwise looks good, and the raw components are clean. I am wondering what c
Electronics Forum | Tue Mar 09 22:26:17 EST 2004 | davef
You should to be soldering to the nickel. The intermetallic is Ni3Sn4. "At relatively low temperatures, the tin-nickel layers form about as rapidly as the tin-copper layers do, but at higher temperatures their growth rate is distinctly lower. At 10
Electronics Forum | Sat Apr 11 09:56:31 EDT 2009 | davef
You're correct. You should expect to see an intermetallic layer in a proper solder connection. Try leaving the component at temperature for a longer period. Growth of intermetallic compounds on Cu surfaces [Klein Wassink]: d = 10^3(exp(-5*10^3/T)t^1
Electronics Forum | Fri Nov 13 14:09:02 EST 1998 | Dave F
| Anyone using SMT "Fair-Rite" beads? We have a P/N 2743019447 that we're using. We need to know the shear force strength of the part and the vendor's man who knows is in Deutschland and can't help until Monday. I can't wait that long. | | Also, do
Electronics Forum | Mon Mar 16 09:02:07 EST 1998 | Justin Medernach
| We are going to try out a PCB manufacturer that has an Alpha Level for ensuring a flat finish on the PCB's. | I am interested to know if anyone has and experiences, either good or bad on how boards treated with this process are to assemble. Is the
Electronics Forum | Fri Aug 27 13:07:44 EDT 2004 | C Lampron
Hello, I believe that the area's of concern are primarily component related. Some component are rated for a temp (usually 260 degrees max) for some length of time. Tant Caps come to mind as being heat sensitive. The other concern would be the inerme
