Abstract
Electronic parts in the automotive, downhole drilling of oil & gas, and aerospace sectors are frequently subjected to severe high strain loads. Those extreme loads may be occurring as a result of shocks, vibrations, and drop-impact circumstances. In addition, these parts are frequently exposed to severe low and high temperatures ranging from −65°C to 200°C. In such critical environment, these electronic equipment can be exposed to strain rates ranging from 1 to 100 per second. SAC solder alloys are the most often used alloys to replace tin-lead solders in electronic assembly applications. Tin, silver, and copper are the essential elements in these lead-free alloys. SAC solder alloys have proven to be successful in surface mount, wave soldering, and hand soldering applications. The primary advantage of RoHS certified lead-free solder is that it is safer than lead solder, which is a severe neurotoxic. 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. Combined effects of higher temperatures and vibrations in electronic components might result in rapid failure. The majority of previous solder joint research has been on either vibrational stresses or thermal cycling for conventional solders like SAC105, and SAC305. SAC alloy failure mechanisms were investigated in this article at higher surrounding test temperatures up to 155°C, as well as at vibration loads of 5g and 10g levels. Harmonic vibrations at the first natural frequency was measured for the test boards with CABGA daisy-chained package at various test temperatures and vibration g-levels. Results on assembly response and resistance were collected utilizing high-speed data acquisition and highspeed imaging. A high-speed camera system was employed to catch the vibration event during testing. Stresses in solder interconnects were calculated using Finite Element Analysis simulation. The impact of g-levels, and operating temperatures on the hysteresis loop and plastic work density has been investigated. The failure mode analysis for the test board has been performed. Anand viscoplasticity material data for the solder alloys which were previously published by authors were used to capture the high-strain rate behavior and temperature dependent aging behavior of the solder junctions for FE analysis.
