| Abstract Scope |
NiTi shape memory alloys (SMAs) offer unique properties but are often limited by high modulus, large hysteresis, and nonlinear stress-strain behavior. One-dimensional (1D) compositional modulation (CM) presents a promising solution by spatially varying transformation temperatures and critical stresses to enhance superelasticity, reduce hysteresis, and achieve ultralow modulus. This study uses phase-field modeling to explore the influence of four key parameters—wavelength, amplitude, wave shape, and alloy composition—on the mechanical response of 1D CM NiTi SMAs. Through analysis of phase transformation kinetics, strain avalanches, and hysteresis, we establish a quantitative processing–structure–property relationship. The results provide a predictive framework for optimizing mechanical performance in CM-based NiTi SMAs. This work advances our quantitative understanding of CM effects on the stress-strain behavior of SMAs and hence guides the design of high-performance SMA and superelastic materials by precise CM engineering using various processing techniques including PVD/CVD/MEB and spinodal/pseudo-spinodal decomposition. |