Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
MM: Fachverband Metall- und Materialphysik
MM 28: Intermetallic Phases I
MM 28.1: Vortrag
Mittwoch, 27. Februar 2008, 17:30–17:45, H 0107
Investigation of lead free soldering reaction between solid Ni and liquid Sn — •Jens Görlich and Guido Schmitz — Institut für Materialphysik, Wilhelm-Klemm-Str.10, D-48149 Münster, Germany
After the ban of lead it is important to understand the reaction mechanisms of new lead free solder systems. We investigated the interreaction between solid Ni and liquid Sn. Reaction times were from 10 seconds to 14 days at 250∘. By scanning electron microscopy we obtained the particle size distributions and determined grain growth of the Ni3Sn4 phase with time. With focused ion beam preparation, we could study the properties of the intermetallic connection layer at the interface Ni/Sn by transmission electron microscopy (TEM) in detail. At short times, the growth rate agrees with the flux driven ripening theory for soldering [1] [2], but for longer times, the time exponent deviates significantly. TEM analysis reveals that the general assumption of constant interface area is not fulfilled at any time. We will compare the experimental data with existing soldering models and present an approach for the growth kinetics of Ni3Sn4 in the Ni/Sn system.(supported by DFG)
[1] K.N. Tu et. al., Physical Review B 66, 115403 (2002)
[2] G. Gosh, J. Appl. Phys. Volume 88, Nr. 11 p.6887