Study on Deformation Behavior and Constitutive Models of Tungsten Alloys Under Electroplastic Effects

The electroplastic effect offers a novel approach to mitigating the room‐temperature brittleness of tungsten alloys, though its deformation mechanism and predictive models remain imperfect. This study investigates tungsten–molybdenum (W–Mo) alloys through pulse‐current‐assisted uniaxial tensile testing, systematically analyzing the influence of varying current densities and pulse frequencies on mechanical properties, supplemented by scanning electron microscopy (SEM) examination of fracture morphologies. To distinguish thermal effects from pure electroplastic effects, air‐cooled control experiments were designed to achieve effective decoupling between the two. Results indicate that appropriate pulse parameters significantly enhance plasticity, with fracture surfaces exhibiting high‐density ductile dimples. Conversely, high energy input induces localized melting, forming ridge‐like fractures that reduce ductility. Concurrently, pulsed current (PC) exhibits a “stiffness adjustment” effect, increasing the material's elastic modulus under high energy conditions. The Joule heating effect primarily reduces flow stresses, whereas the purely electrical plastic effect dominates in microstructural regulation and performance optimization. An improved Johnson–Cook (JC) constitutive model, constructed based on experimental data, accurately describes deformation behavior under current loading. Predictions exhibit high agreement with experiments, with MAPE reduced by 93.4% and root mean square error (RMSE) decreased by 95.9% compared to the original model. This study provides theoretical foundations for electrical‐assisted forming of tungsten alloys and model development.