Phase Transformations and Mechanical Properties in In–Bi–Sn Alloys as a Result of Low-Temperature Storage
Jiye Zhou,
Xin Fu Tan,
Stuart D. McDonald,
Kazuhiro Nogita
Affiliations
Jiye Zhou
Nihon Superior Centre for the Manufacture of Electronic Materials (NS CMEM), School of Mechanical and Mining Engineering, The University of Queensland, St. Lucia, QLD 4072, Australia
Xin Fu Tan
Nihon Superior Centre for the Manufacture of Electronic Materials (NS CMEM), School of Mechanical and Mining Engineering, The University of Queensland, St. Lucia, QLD 4072, Australia
Stuart D. McDonald
Nihon Superior Centre for the Manufacture of Electronic Materials (NS CMEM), School of Mechanical and Mining Engineering, The University of Queensland, St. Lucia, QLD 4072, Australia
Kazuhiro Nogita
Nihon Superior Centre for the Manufacture of Electronic Materials (NS CMEM), School of Mechanical and Mining Engineering, The University of Queensland, St. Lucia, QLD 4072, Australia
The In–Bi–Sn low-temperature solder alloys are regarded as potential candidates for cryogenic and space exploration applications. This study investigates the variations in the mechanical properties and microstructures of two different compositions: In15wt%Bi35wt%Sn and In30wt%Bi20wt%Sn, after exposure to a low-temperature environment (−20 °C) for 10 months. An increase in the ultimate tensile strength was observed across all the tested samples and a decrease in elongation to failure was observed in In30wt%Bi20wt%Sn. Changes in the microstructure were identified through scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD). The impact of this low-temperature environment is described, considering the varying proportions and compositions of the three phases (BiIn2(Sn), γ-InSn4(Bi), and β-In3Sn(Bi)) present within the alloys and their contribution to the mechanical properties.