Combined loading and failure analysis of lead-free solder joints due to creep and fatigue phenomena

Purpose – The aim of this work is the use of specially designed, authoring device to evaluate the strength of solder alloys commonly used in all kinds of electronic and electrical devices that are used in various fields of economic and industrial development to shorten the testing period. By obtaining answers to pervade science questions on how to properly investigate the reliability of solder joints can increase lifespan (uptime) of all electronic devices, and especially those that are used in the process submitted severe external conditions (dust, humidity air, heat, mechanical stress). Design/methodology/approach – The basic demand for performing the experimental tests is to measure small displacements (order of fractions of micrometers or of single microns) occurring within the sample. The analysis of the displacement values in various environmental conditions (temperature, humidity, current flow) allows estimating how a given material behaves also in a longer time, under normal operating conditions. Unlike a commonly used method, based on measuring the time-to-failure, at which the item is damaged due to accelerated aging, a behaviour of the sample is being tested for the selected duration time and the given loading conditions. Findings – The theoretical analysis and performed numerical simulations of ATC tests based on developed failure and reliability investigation system (FRIS) imply proposed here combined loading approach a promising and affective method for accelerated reliability tests. Both indentation and FRIS techniques by numerous possibilities of loading conditions seem to be appropriate in order to study the creep and fatigue behaviour. That kind of behaviours can be used by different models which characterize separately the mechanical properties under creep or fatigue tests. In case of creep mode, the displacement is expressed as a function of time where different parameters can be used to represent the creep sensibility. Originality/value – New device can provide both creep and fatigue phenomena simultaneously and perform tests in digital controlled environmental conditions. That approach enables faster method for testing reliability of solder joints.