Electrical and Thermal Characterisation of Millscale Modified Sn-Cu Lead-Free Solders
No Thumbnail Available
Files
Date
2019
Authors
Sekunowo, O.
Durowaye, S.
Fashakin, G.
Journal Title
Journal ISSN
Volume Title
Publisher
Journal of the Institute of Engineering.
Abstract
Lead-free solders are gaining much attention as a result of legislation
against the inclusion of lead and other hazardous materials in solders used in
joining electronic components. This study investigated the effect of iron millscale
(IMS) modified tin-copper (Sn-Cu) alloy on the electrical resistivity, electrical,
and thermal conductivities of the solder samples under increasing applied current.
The input materials consist of tin, zinc and iron millscale while the copper was
varied from 0.2 – 1.0 wt. %. Fabrication of the alloy employed metal casting
technique followed by relevant test samples preparation for characterisation in
terms of microstructure, electrical, and thermal conductivities. Results show that
the sample with 1 wt. % Cu addition exhibited the highest electrical and thermal
conductivity values of 9967.9 S/m and 11.24 x 10-5 W/mK respectively at applied
current value of 600 A with the lowest resistivity of 1 x 10-4 (Ωm). The solder
alloy microstructure confirmed the presence of Cu6Sn5-FeO intermetallic phase
dispersed in Sn matrix forming a continuous network. Contribution to the overall
desirable performance of the solder alloy may have stemmed from the strong and
coherent inter-crystal cohesion between the Cu6Sn3 and FeO phases which resulted
in improved electrical and thermal conductivities of the as cast solder. The grade of
solder alloy fabricated is adjudged suitable for assembling electronic components
in industrial plant control panels.
Description
Keywords
Lead-free solder, iron millscale, microstructure, electrical property, thermal property
Citation
Journal of the Institute of Engineering; 15(1): 38-47