High-pressure torsion

High-pressure torsion (HPT) is a severe plastic deformation technique used to refine the microstructure of materials by applying both high pressure and torsional strain. It was introduced in 1935 by P.W. Bridgman, who developed early methods to apply extreme strain under high pressures in material processing. HPT involves compressing a material between two anvils while simultaneously rotating one of the anvils, inducing shear deformation. Today, HPT is widely used in materials science to create ultrafine-grained and nanostructured metallic and non-metallic materials, control phase transformations, synthesize new materials or investigate mechanisms underlying some natural phenomena. This process leads to significant grain refinement, resulting in materials with enhanced mechanical properties such as increased tensile strength and hardness. It has also applications in producing metals with enhanced superplasticity, improving the toughness of alloys, and creating materials with unique properties like high wear resistance. Researchers also use HPT to study fundamental aspects of deformation and phase transition under extreme conditions. Additionally, HPT is being explored for potential applications in the energy field. Progress in HPT science and technology continues to open new possibilities in the development of advanced materials with superior properties.