Issue link: https://iconnect007.uberflip.com/i/1493016
REAL TIME WITH... IPC APEX EXPO 2023 SHOW & TELL MAGAZINE I I-CONNECT007 55 REAL TIME WITH... IPC APEX EXPO 2023 SHOW & TELL MAGAZINE I I-CONNECT007 55 We had those elements integrated and we were measuring the distance and difference in voltage. We considered the change of points we could see—like what temperature change we had—and we also did this over time. We were not just cutting in one-step strips requir- ing multiple iterations of cutting through the material; we did around 20 micrometers of material with each iteration, but very, very fast. All the while, of course, the temperature was increasing, and we could see the tem- perature continuing to increase over time. It was interesting to see what setting points the temperatures reached. This is a key element for heat sensitive components close to the cut- ting channel. You want to know what kind of temperatures you can expect there. The tem- perature in the substrate is key to the quality of the cutting edge, so you don't want to reach a certain temperature level, because then the material starts to carbonize. Sounds like there are some potential practical applications for this research. Where do you see this being used by industry in the future? Lasers are already widely used, but there are still some concerns regarding the temperature. Temperature is the first thing that comes to mind when you're thinking about laser tech- nology. We wanted to prove that we don't have such high temperatures close to the cutting channel, because then we can widen the range of applications. It makes it more attractive for more customers. It helps to know how wide the temperature safety margins are close to where the laser is doing its work. Not only does it help manufacturing, but that's a consideration designers can work with. Perhaps the danger zone is much smaller than most people realize. The closest temperature we measured was approximately 100 micrometers away from the cutting channel. Even there, the temperature is comparable to the temperatures in the reflow oven, and well under the liquidus temperature of the alloys, so they can't start to melt. Even if we are 100 micrometers close to the cutting, that's important to know, because then we won't have components meeting right next to the cutting. Do you intend to continue this research? We tested 1.6 millimeter and FR-4 substrate, which is quite stable. But of course, we also want to look at the material thickness. We need multiple iterations. We also want to have a look at other effects under other circumstances, which might also have effects on the tempera- ture behavior. I suppose we also observed that if we have copper, we can more successfully wick the heat away because it's a good heat conductor. Knowing that also helps a lot. We have a good start here, and some very interesting insights already in this paper, but we definitely want do more research. Patrick, thank you. Quite interesting. Congratulations once again. You're welcome. S&T IPC Best Technical Paper Award