Behavior of Tin Electro-deposition and Spontaneous Tin Alloy Formation on Nickel Flash-coated Steel Surface

Abstract

The behavior of β-Sn electro-deposition and successive spontaneous Ni-Sn alloy formation on Ni flash-coated steel surface were studied for the development of low tin plated steel sheet for the welded can production. The results are as follows :
1) The crystal orientation of deposited β-Sn on Ni flash-coated steel surface shows a very strong preference for β-Sn(200) plane.
2) The Ni-Sn alloy formation occurs spontaneouly at Sn/Fe interface during the electro-deposition. After the deposition, the alloy formation proceeds during aging at room temperature and reaches a saturated amount.
3) The chemical composition of the saturated Ni-Sn alloy shows the Sn/Ni mass ratio of 6.5.
4) From the stoichiometric examination and the crystallographic determination it is concluded that the saturated Ni-Sn alloy is composed of Ni₃Sn, Ni₃Sn₂ and amorphous β-Sn.