This Small Business Innovative Research Phase I project focuses on the computational design of a new class of shape memory alloys (SMAs ). In this project advanced computational design methodology will be used to incorporate precipitation strengthening and demonstrate the feasibility of computationally designing a nanostructured high performance nickel titanium (NiTi) SMA. The computational tools, based on thermodynamic and mechanistic modeling, will be extended to predict the nanoscale Heusler precipitation microstructure and strengthening within a NiTi matrix. Reversible thermoelastic transformation of the matrix will be modeled with multicomponent thermodynamic modeling and martensitic interfacial mobility theory. Integrating the extended models, the predictive design of novel high strength SMAs will be undertaken by assessing various design strategies and trade-offs. Commercially, the most common SMAs are monolithic NiTi, having a wide range of use in markets representing billions of dollars. However, along with copper-based SMAs, they have been empirically optimized to their limits and the true economic potential has yet to be realized. This approach promises to lead to the production of robust SMAs, with fundamentally designed characteristics, possessing longer cyclic lifetime and superior performance for both thin film and bulk applications.
