Electronics Forum | Tue Jul 30 10:04:51 EDT 2002 | dason_c
Dave, I am very interesting to know about the dewetting or pull back, we are currently use the uP78 paste. Will nitrogen, profile setting help to reduce the dewetting. Thank.
Electronics Forum | Thu May 25 09:09:43 EDT 2006 | cobar
Had the same problem with a batch of 0603`s nfrom Vishay. They eventually replaced the components after I proved that the problem was with the component.
Electronics Forum | Tue Jul 30 08:37:39 EDT 2002 | davef
When you talk about 'poor wetting', 'dewett', 'no wets', etc.; are you seeing solder pulling back or away from the pad? Please describe the condition. Dewetting. The condition in the solder joint in which the liquid solder has not adhered intimate
Electronics Forum | Mon May 22 18:19:29 EDT 2006 | Steve
I have read some threads about poor wetting on palladium-silver (Pd-Ag) coated components. I followed the suggestions, but I am still having a problem. The part is an 0603 chip type (Vishay varistor). The Process: solder paste is lead-free Alpha Met
Electronics Forum | Tue Jul 30 12:15:15 EDT 2002 | Rick Lathrop
Hi Dave, The paste applied to the board ends up on the tombstone. The pad has a thin covering of solder most of the time, this is why I think they call it a dewet. Occasionally the pad shows some areas of gold and very rarely are some pads not wet at
Electronics Forum | Tue May 23 09:16:57 EDT 2006 | Steve
Had exactly the same type of issues. Tried everything from pre fluxing the pcb's , various ammendements to the oven profile and various pastes. Finally after a lot of help from multicore we settled on a paste by the code of cr39. A no clean flux wit
Electronics Forum | Tue May 23 09:36:11 EDT 2006 | Steve
Not being funny here but I understand exactly what you are saying and sounds exactly the same as we experienced. Seriously try a different paste. Give Tamura a ring and I am sure they will give you a sample. I don't have the exact part code but they
Electronics Forum | Wed May 24 16:57:23 EDT 2006 | Steve
The temperatures were measured on the board, ~1/2" away from the components in question. Admittedly the profile is on the bottom end of the Alpha recommendations. The profile was set up this way intentionally to avoid heat damage to other components
Electronics Forum | Thu May 25 03:31:17 EDT 2006 | slaine
Hi I manufacture ceramic parts that have a terminations that are palladium/platinum/silver or any combination of the 3. Termination Ink usually consists of 3 main parts the alloy, glass frit and binder. Binder is to help bind everything together whi
Electronics Forum | Thu Aug 01 08:58:47 EDT 2002 | Rick Lathrop
Good morning Dave F. I am not going to try to touchup the solder pad until I get surface analysis work done, don't want to ruin the evidence. I am getting XPS work done not XRF, XPS is X-ray Photoelectron Spectroscopy and can see very thin films of o