Abstract
In the automotive, oil & gas, aerospace, and medical technology sectors, electronic parts are frequently subjected to higher strain loads as a result of shocks, vibrations, and drop-impact circumstances. The electrical parts in such applications are frequently exposed to severe low and high temperatures ranging from −65°C to 200°C. Furthermore, in the critical environment, these electronic equipment can be exposed to high strain rates ranging from 1 to 100 per second. SAC solder alloys are the primary alloys used to replace tin-lead solders in electronic assembly applications. Surface mount, wave soldering, and hand soldering applications have all demonstrated the effectiveness of SAC solder alloys. Numerous doped solder alloys, such as SAC-Q, SAC-R, Innolot, M758 etc. have recently been introduced in electronic components. Mechanical characteristics and statistics for lead-free solder alloys are critical for enhancing electronic package durability at high temperatures and strain rates. Additionally, thermal aging causes microstructure changes, and can significantly affect the mechanical characteristics of solder alloys. There are not enough results are available for the mechanical properties of solder alloys with extreme low to high working temperatures. Additionally, there is currently a lack of published literature on the mechanical performance of lead-free alloys under the harsh conditions of high-temperature vibration, drop, and shock. SAC Solders are tested and examined for this study at working temperatures ranging from −65°C to 200°C and at strain rates of up to 75 per second for up to 1 year of isothermal aging with a storage temperature of 100°C. Also, the obtained experimental findings and data were fitted to the Anand viscoplasticity model, and the Anand constants were determined by calculating the stress-strain behavior reported for operating temperatures ranging from −65°C to +200°C. In addition, FE analysis for drop/shock events for 1500g, for BGA package assembly with PCB has been performed. Hysteresis stress-strain curves and plastic work density curves for the solder ball joints are examined under various thermal aging circumstances for drop/shock events. Effect of various operating temperatures and aging durations on hysteresis loops and plastic work densities have been studied.
