Microstructural and tensile properties of Fe and Bi added Sn-1Ag-0.5Cu solder alloy under high temperature environment

Corrosion insight of iron and bismuth added Sn–1Ag–0.5Cu lead-free solder alloy

“…In these cases, FeSn 2 IMC particles were also disclosed, in addition to Ag 3 Sn and Cu 6 Sn 5 particles. This shows that in the presence of Fe some of it forms FeSn 2 IMC particles, while the rest can distribute as insoluble particles in the matrix [8,26]. The incorporation of Fe can also control the particle size of the Ag 3 Sn and Cu 6 Sn 5 [27].…”

“…In comparison with the soft Sn matrix, Ag/Cu-rich IMC particles are naturally strong and brittle. Thus, the formation and distribution of IMCs can play an important role in improving the mechanical behaviour of the lead-free solder alloys, where the smaller IMCs particles result in improved strengthening effect in the solder due to more higher barriers per unit area to the slipping of dislocations [8,30]. For SAC105–Fe–1Bi alloy, EDS spectra of spot 4 shows the co-existence of Sn and Fe that led to the development of FeSn 2 IMC particles in inter-dendritic regions.…”

“…Meanwhile, few studies reported that small additions of Fe enhance the elastic compliance and plastic energy dissipation capacity of the solder [13]. Our group also found that the addition of both Fe and Bi to SAC105 solder alloy can modify the microstructure and thereby can improve its physical properties and mechanical performance [8]. Nevertheless, with the massive production and application of microelectronics comprising lead-free solder servicing at locations ranging from mild to hostile environments, more attention should be paid on the corrosion behaviour of lead-free solder alloys [14,15], where the IMCs formation like Ag 3 Sn and Cu 6 Sn 5 can adversely affect the corrosion resistance, fatigue life, and mechanical properties [5].…”

“…The procedure for solder alloys preparation followed our previously described protocol [8]. In summary, the samples were prepared from pure metals (tin, silver, copper, iron, and bismuth) in the form of ingots.…”

“…Owing to its near-eutectic composition, low melting temperature, good wettability and superior mechanical properties, Sn-Ag-Cu (SAC) based alloys are recognised as one of the promising lead-free candidates [8,9]. Thus, many efforts are made in the development of various SAC solder alloys in order to reduce the silver content and the final cost [10,11].…”