Size and microstructure effects on the stress-strain behaviour of lead-free solder joints

The properties of lead-free solders such as Sn3.8Ag0.7Cu are less understood than traditional Sn-Pb solders, as well as the factors affecting these material properties. Therefore, the present paper focuses on determination of stress-strain properties for both small-scale solder joints and for bulk solder for three different strain rates. The paper also analyses the obtained experimental results, and compares material properties between the solder joint and the bulk solder. The reasons for the differences in the observed material properties are discussed, and their effects are separated through the use of finite-element analysis.