Galvanic corrosion analysis of a Bi-Zn solder alloy coupled to Ni and Cu substrates

Author(s)

Septimio, Rudimylla S. ; Arenas, Maria A. ; Conde, Ana ; Garcia, Amauri ; Cheung, Noe ; de Damborenea, Juan

• Document type: Journal article
• Source: CORROSION ENGINEERING SCIENCE AND TECHNOLOGY; v. 55, n. 8, p. 10-pg., 2020-07-07.

Abstract

Corrosion has become a frequent and significant issue in the electronics industry. For this reason, galvanic corrosion of soldered joints, i.e. when solder alloys are in contact with a metallic substrate, is so important. The present study aims to investigate the corrosion behaviour of the Bi-2.7wt-%Zn solder alloy when in contact with Cu and Ni substrates in a 0.06M NaCl solution. Polarisation curves show that Ni and Cu have nobler behaviour than the Bi-Zn alloy. However, although the Bi-Zn alloy exhibits active corrosion behaviour, the open circuit potential tends to shift toward more positive potentials over time. The galvanic current densities (i(galv)) of both Bi-Zn alloy/Ni and Cu couples are initially similar and three times higher than the corrosion current density of the Bi-Zn alloy. However, the couples show a decrease ini(galv.), with time and the couple formed with Ni has produced the lowest galvanic current density. (AU)

• FAPESP's process: 17/15158-0 - Characterization of microstructure and properties in the evaluation of alloys for thermal interface contact
• Grantee: Amauri Garcia
• Support Opportunities: Regular Research Grants
• FAPESP's process: 17/16058-9 - Solidification Microstructures and Wear Resistance of Zn-Al-Bi Monotectic Alloys
• Grantee: Noe Cheung
• Support Opportunities: Scholarships abroad - Research