Electroplasticity
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Electroplasticity, describes the enhanced plastic behavior of a solid material under the application of an electric field.[1] This electric field could be internal, resulting in current flow in conducting materials, or external. The effect of electric field on mechanical properties ranges from simply enhancing existing plasticity, such as reducing the flow stress in already ductile metals, to promoting plasticity in otherwise brittle ceramics. The exact mechanisms that control electroplasticity vary based on the material and the exact conditions (e.g., temperature, strain rate, grain size, etc.). Enhancing the plasticity of materials is of great practical interest as plastic deformation provides an efficient way of transforming raw materials into final products. The use of electroplasticity to improve processing of materials is known as electrically assisted manufacturing.
Electroplasticity was first discovered by Eugene S. Machlin, who reported in 1959 that applying an electric field made NaCl weaker and more ductile.[2] Since then, the effect of electric fields on plasticity has been studied in many materials systems including metal, ceramics, and semiconductors. Various mechanisms have been posited to explain electroplastic effects and their dependence on materials properties and external conditions. For most materials the electroplastic effect arises from a combination of multiple mechanisms. This should not be all that surprising given that the electric fields directly affect electrons which dictate the bonding in materials and therefore all higher level phenomena such as dislocation motion, flow stress, vacancy diffusion, etc.