Cerium as corrosion inhibitor for Sn–3Ag–0.5Cu solder alloy in 3.5% NaCl solution

The investigation was conducted to study the corrosion inhibition performance of cerium as an inhibitor for Sn–3Ag–0.5Cu (SAC305) lead-free solder alloy in 3.5% NaCl solution. The investigation is useful to suggest an inhibitor for SAC305 solder for microelectronic applications in marine environments. Weight loss measurement results for 30 °C showed the maximum inhibition efficiency as 33.33% when 700 ppm of cerium were added to 3.5% NaCl solution. However, polarization experiments displayed a better corrosion resistance for the alloy in 3.5% NaCl solution at 700 ppm of inhibitor concentration almost at all higher temperatures (40 and 50 °C). At room temperature, the corrosion rate decreases at 700 ppm, indicating that a high inhibitor concentration increases protective efficacy. Hence, cerium appeared to be a capable inhibitor for the alloy under the NaCl acidic environment.