As we are all aware the lead-free movement has been somewhat popular lately. We have had in depth discussions about materials, processes and procedures. How about training or re-training? I believe this would be one of the biggest challenges facing the lead-free transition, if it should happen. What do you have in mind as far as re-training is concerned for the use of lead free solders? We would obviously need new standards, new criteria and new way to look at solder connections from both an esthetical and reliability standpoints. What comments or recommendations do you have for these issues? A response is appreciated.
Deon, my first response is YES - big time. You are correct that there are some massive issues here.
For one thing, lead free solders are only one solution, as conductive epoxy has also been put forward. This was demonstrated on the TAC line at Nepcon West, and some of the potential problems were very evident.
But standards come first. From my understanding, which is minimal on the technical side of the issue, lead-free alloy formulations behave in a similar way to conventional eutectic lead-based solders, but issues of coverage might arise, as joint strength characteristics are different. Process temperatures are higher, which also affects susceptibility to humidity related defects - requiring more attention to component handling for moisture sensitive parts. Rework may be a new ball game as well.
I believe that in North America the standards issues are being addressed by organizations like NEMI, IPC, and so on. The training has to follow the standards development process. At the same time, the solder manufacturers will be looking for competitive advantage, and new products and processes can be expected to occur at a fairly rapid pace if lead-free is seen as inevitable.
I concur with your comment that training and retraining will be one of the biggest challenges in the transition. The only way to stay ahead of the curve is to stay in close touch with the standards development process.