Low Cycle Fatigue Behavior of Sn-4.0Ag-0.5Cu Lead-free Solder Joints in Different Corrosive Environmental Conditions

Isothermal low cycle fatigue experiments of lead free Sn-Ag-Cu solder joints were executed in different corrosive environmental conditions. The environments/factors varied were temperature, humidity and salt application on to the solder joints. The experiments were executed according to a full factorial design of experiments where the three different factors and two levels for each factor were varied according to literature. The outcome of the design of experiments was the number of cycles to failure defined as 50% load drop. The main goal with this work was to analyze the fatigue behavior of this solder material as a function of the different corrosive environments, and simultaneously to analyze its corrosion behavior/resistance. The factor with the highest effect on the fatigue life was salt application followed by temperature. The factor humidity was not significant for the tests performed