Influence of bismuth (Bi) addition on wetting characteristics of Sn-3Ag-0.5Cu solder alloy on Cu substrate

• Published in: Engineering science and technology, an international journal an international journal, 2018-12, Vol.21 (6), p.1159-1163
• Main Authors: Erer, Ahmet Mustafa, Oguz, Serkan, Türen, Yunus
• Format: Article
• Language: English
• Subjects: Contact angle; Pb-free solder alloy; Wettability
• ISSN: 2215-0986; 2215-0986
• DOI: 10.1016/j.jestch.2018.10.002

This work investigates the effect of bismuth (Bi) addition, 1 wt% Bi, on wettability of the Sn-3.0Ag-0.5Cu (SAC305) ternary Pb-free solder alloy. Adding Bi to SAC305 decreased the contact angles (θ) of the Sn-2.0Ag-0.5Cu-1.0Bi (SAC-1Bi) quaternary Pb-free solder alloy, which were measured by using of the sessile drop method at various temperatures (250, 280 and 310 °C) on Cu substrate in argon (Ar) atmosphere. Microstructures, inter-metallic phases and melting temperatures were analyzed by optical microscope, scanning electron microscopy, X-ray diffraction, and differential scanning calorimetry, and effects of the amount of Bi on microstructure were investigated. The experimental results exhibited that when the addition of Bi was 1 wt%, changing in melting temperature of SAC-1Bi solder was insignificant, but the wetting angles (θ) of the solder alloy decreased which were measured by using of the sessile drop method at various temperatures. The lowest θ was obtained as 35.6° for SAC-1Bi alloy at 310 °C.