Interfacial Energy and Wetting of Cu/Sn-Pb Alloy

Wetting of Sn-Pb Alloys on Cu Plate (2)

Abstract

In wetting phenomena, interfacial energy between liquid and solid is of importance. We investigated the structure of Cu/Pb-Sn interface and estimated interfacial energy on the bases of the experimental results, and discussed the wetting mechanism.
The followings were inferred from the results. The spreading of halo depends on the amount of intermetallic compound formed at the solid/liquid interface which varies interfacial energy. The supplied liquid from droplet into a halo lowers the concentration of intermetallic compound and promotes spreading of halo. The spreading of drop let depends on the spreading of halo which lowers surface energy of solid for the spreading of drop let. At an equilibrium state of intermetallic compound formation and liquid supply from droplet, the spreading stops by means of that work of spread becomes zero.
The tendency of spreading of Pb-Sn alloys on Cu plate estimated from the phenomena above mentioned showed good agreement with the well known spreading phenomena.