Issue link: https://iconnect007.uberflip.com/i/806706
12 SMT Magazine • April 2017 by Stephen Las Marias I-CONNECT007 Industry veteran Happy Holden and Saline Lectronics Senior Process Engineer Cathy Cox, discuss the various challenges and issues that users face in soldering, including the lack of a 'one-size-fits-all' approach in the process, and some key factors that the PCB assembly indus- try should consider when it comes to different applications and markets. Stephen Las Marias: What do you think are the greatest challenges when it comes to soldering in PCB assembly? Cathy Cox: I would have to say our challenges are temperature. Temperature is a big problem with the flex boards. With the circuit board be- ing so thin, actually getting the right tempera- ture to be able to run them through a reflow is definitely a challenge. Happy Holden: Picking a final finish that's com- patible with the solder that you picked in the flux. There's no one answer that fits all. So pick- ing that, and then you might say defending it—when people are selling different combina- tions—is a pretty big challenge, especially when not all the criteria for evaluation and testing is readily available. I've come to learn that the wetting balance really isn't reliable to use that much anymore. Our end-use applications are so diverse that when you talk about any particular subject, it's tough for people to apply. 'Does this apply to me or is he talking about the other guy over there?' For instance, flex assembly and solder- ing is a particular challenge; but when I think of soldering, I think of rigid boards and I think of standard size thinner ones. When you get to really thick—over 2 mm—type boards, getting lead-free solder up to a milling temperature is a real challenge. There, you have to worry about the materials you built the boards for. It's a huge industry, and how you carve it up is part of the challenge. My life for years has been in automotive electronics. The company I work for is one of the highest volume assembler of automotive electronics in the Western hemisphere. Solder- ing is not really a problem except for new de- The Complex World of SOLDERING FEATURE INTERVIEW