2026년 08월 24일

Low-temperature solder paste—specifically Sn42Bi57 (tin-bismuth)—reflows at around 170°C instead of the standard 240°C for SAC305. That 70-degree difference means less board warpage, happier heat-sensitive components, and lower energy bills. But there’s a trade-off: Sn-Bi joints are more brittle and require careful validation before production. This guide covers alloy basics, reflow profiles, real-world applications, and a practical selection framework to help you decide if low-temp paste makes sense for your SMT line.