2025 Serin Sn Cu Al Mg Thermal Fatigue

In the present study, lead-free Sn–Cu–Al–Mg-based solder alloys for electronics packaging were produced. Effects of thermal shock and thermal stress on the crack formation in the Sn-based solder alloys were investigated. Lead-free quaternary Sn–Cu–Al–Mg-based solder alloys were produced by using mechanical alloying and powder metallurgy route. Soldering involves using a molten filler metal to wet the surfaces of a joint. Wave soldering is a method for mass assembly of printed circuit boards involving through holes. Mechanical alloying and powder metallurgy methods were utilized to prevent formation of intermetallics and voids, achieving a homogeneous microstructure. Initially, elemental metal powders were mechanically alloyed, followed by compacting at 300 MPa and sintering at 180 °C for 60 min. Nondestructive ultrasonic and eddy current tests characterized the solder alloy specimens, determining elastic modulus and electrical conductivity, respectively. Microstructure was examined via scanning electron microscopy. The effects of thermal shock and thermal stress on the crack formation were studied through specific heating cycles. Electrochemical corrosion behavior of the alloys was assessed in a NaCl solution. The combination of methodologies provides critical insights into the mechanical and thermal characteristics of these lead-free solder alloys.