Vol. 7, Issue 1, Part B (2025)

Shape memory alloys as a class of smart materials, exhibit unique thermomechanical behavior governed by reversible martensitic and austenitic phase transformations. Their functional reliability depends significantly on thermodynamic parameters such as entropy, enthalpy, and free energy, which collectively influence transformation temperatures, thermal hysteresis, and phase stability. NiTi-based SMAs dominate due to their consistent superelasticity and shape recovery, while Cu-based and Fe-based systems offer cost-effectiveness and high strength but face limitations in cyclic stability and transformation consistency. Recent advances in high-entropy SMAs have demonstrated improved thermal stability and reduced energy dissipation, making them suitable for high-temperature and high-stress applications. Data-driven thermodynamic models and computational approaches are emerging as critical tools to refine transformation predictions and optimize functional properties. Understanding these thermodynamic mechanisms provides a foundation for designing SMAs with improved durability, energy efficiency, and tailored performance for biomedical, aerospace, and robotic applications. Thermodynamic insights remain crucial for enhancing SMA reliability and functional precision in diverse engineering applications.