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Indexed by:期刊论文

Date of Publication:2011-01-01

Journal:Journal of the Chinese Society of Corrosion and Protection

Included Journals:PKU、ISTIC、Scopus

Volume:31

Issue:4

Page Number:381-384+388

ISSN No.:10054537

Abstract:Leaching behavior of Sn-3.5Ag-0.75Cu and Sn-0.75Cu lead-free solder alloys in a NaCl-na2so4- na2co3 mixed solution as simulated soil was investigated and compared with that of Sn-37Pb alloy. The results showed that leaching amount of Sn from the three solders increased with reaction period. The most leaching amount of Sn was found for Sn-0.7Cu solder alloy. However, Sn leached from Sn-3.5Ag-0.75Cu solder alloy was depressed by adding Ag element. The leaching amount of Ag, Cu and Pb elements also increased linearly with increasing time. However, the relatively less amount of leached Ag and Cu was measured. The product on the leached solder alloy surface was identified as Sn4 (OH) 6Cl2 and SnO. Many cracks and pits were found in the product on Sn-0.75Cu alloy surface, while the product layer on Sn-3.5Ag-0.75Cu alloy was rather compact. For Sn-37Pb alloy, some product had spalled from the surface. Based on the experimental results, it was supposed that the phase formation and morphology of surface product were responsible for the difference of leaching kinetics for these three solder alloys.