| Abstract Scope |
Tungsten (W) is a leading candidate for fusion energy systems, but its intrinsic brittleness and high ductile-to-brittle transition temperature (DBTT) constrain the in-service performance. In this study, we present an integrated, computationally guided strategy for designing W-based multi-principal element alloys (MPEAs) with improved mechanical resilience. The framework combines first-principles thermodynamic modelling, electronic-structure calculations, machine-learning predictions of ductility, dislocation modeling, and experimental validation to quantify how phase stability, elastic stiffness, and plasticity emerge from coupled electronic and lattice mechanisms. W-V-rich compositions form strongly stabilized BCC solid solutions, while controlled Ti additions improve ductility without sacrificing solid-solution strengthening. An optimized composition window, W30-50Ti10-20V40-60, exhibits high stiffness, yield strength, and ductility with moderated Peierls stress. Pre-irradiation mechanical testing, including Rockwell indentation, confirms enhanced plastic accommodation relative to pure W. These results establish an electronic-structure-driven framework for designing mechanically robust W alloys for fusion first-wall applications. |
