pISSN : 1598-706X / eISSN : 2288-8381
한국주조공학회지 (22권1호 35-41)
Manufacturing of Composite Solders by an In-situ Process
In-situ 공정에 의한 복합솔더 제조
Seong-Yong Hwang, Joo-Won Lee, Zin-Hyoung Lee
To improve the reliability of solder joints, a composite solder which consists of solder matrix and intermetallic reinforcements was manufactured by a new method. The cast ingot of Sn-6.9Cu-2.9Ag alloy had primary Cu6Sn5 intermetallics in the form of dendrites. After rolling the ingot, the intermetallic dendrites were crushed into fine particles and distributed uniformly throughout the solder matrix. As the rolled strips became thinner, the average size of the crushed particles reached a critical size which did not decrease any more by further rolling. The critical size was nearly the same as the average width of intermetallic dendrite trunk. The crushed intermetallic particles did not melt and remained in solid state during reflow soldering due to their high meltingterm-perature. The coarsening and gravitational segregation of the particles were observed during reflow soldering.
composite, solder, Cu6Sn5, intermetallic, particle, reflow