NON-TECHNICAL SUMMARY Dislocation, a type of crystalline defect caused by the linear misalignment of atoms, plays a crucial role in determining the mechanical properties of metallic materials during processing and service. This Faculty Early Career Development (CAREER) award supports a research and education project aimed at understanding how dislocations move and how their motion affects the deformation behavior of a class of materials known as concentrated solid-solution alloys (CSAs). In CSAs, different atomic species are randomly mixed in high concentrations, creating locally varied chemical compositions throughout the crystal lattice and spatially fluctuated energy barriers to dislocation motion. These unique atomic-scale features cause dislocations in CSAs to behave differently from those in traditional alloys, leading to mechanical characteristics that are not yet fully understood. This research project integrates statistical theories, computational modeling, and experimental validation to develop a framework for quantitative predictions of dislocation motion in CSAs. By focusing on CSAs made from multiple refractory metals like niobium, molybdenum and tungsten, the project aims to reveal how local chemical fluctuations influence dislocation motion and how these mechanisms shape the strength and plasticity of CSAs. The knowledge being generated could lead to new design strategies for novel refractory alloys with superior mechanical properties and room-temperature pr