Temperature and NaCl deposition dependent corrosion of SAC305 solder alloy in simulated marine atmosphere

The stable operation of electronic devices in marine atmospheric environment is affected by the corrosion deterioration of solder joints, and the effects by atmosphere temperature and chloride deposition are critical. In this work, NaCl deposition and temperature dependent corrosion of Pb-free SAC305 solder in simulated marine atmosphere has been investigated. The results indicate that higher NaCl deposition prolongs the surface wetting time and leads to the final thicker saturated electrolyte film for further corrosion. Higher temperature accelerates the evaporation and contributes to the final thinner saturated NaCl electrolyte film. Besides, the corrosion control process varies under the initially covered thicker NaCl electrolyte layer and under the final saturated much thinner NaCl electrolyte film as the evaporation proceeds. Moreover, the ready oxygen availability through the final thinner saturated NaCl electrolyte film facilitates the formation of corrosion product layer mainly of electrochemically stable SnO2, but higher temperature leads to the final corrosion product layer with smaller crystal size and large cracks. The findings clearly demonstrate the effects of NaCl deposition and temperature on corrosion evolution of SAC305 solder joints and are critical to the daily maintenance of electronic devices for longer service life in marine atmosphere. (C) 2021 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

Automated summary

The research found that NaCl deposition and temperature have significant effects on the corrosion evolution of SAC305 solder joints, with high NaCl deposition prolonging the corrosion process, high temperature accelerating evaporation and leading to thinner film formation, affecting the formation of corrosion product layer.