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The fully pearlitic rail steel R260 was deformed by equal channel angular pressing at room temperature. Changes in the microstructure as well as changes in mechanical properties were determined. With increasing predeformation significant changes of the tensile strength, the fatigue crack propagation rate and the fracture toughness occurred. Due to the alignment of the cementite lamellae, also a markedly anisotropy in all these properties evolved.

Severe plastic deformation has been applied to Armco iron and copper by means of high pressure torsion. The evolution of the shear stress during deformation was measured under different hydrostatic pressures. By applying a simple model for a strain hardening, the shear stress–shear strain curves are fitted and the influence of the hydrostatic pressure is studied. These results are compared to microhardness measurements, tensile strength and the microstructural evolution.

Pure copper is deformed by high pressure torsion and the resulting microstructure is studied. Small structural elements are formed. Their size decreases with increasing strain and reach a steady-state. The misorientation between neighbouring structural elements increases with strain and finally reaches a nearly random distribution. The steady-state size decreases with increasing pressure and decreasing temperature. The shape of the elements suggests the continuous formation of new elements during steady-state deformation. This would be a process similar to dynamic recrystallisation.

The rail steel S900A and Armco-iron have been deformed by severe plastic deformation, the microstructural evolution and the changes in microhardness have been investigated. In both materials the deformation leads to a decrease in structure size. In the case of the steel an alignment of the lamellae parallel to the shear plane and a decrease of the lamellae spacing is observed. Lamellae which have been originally not favourably aligned are heavily bent and broken into small fragments. This refinement is also reflected in the evolution of the microhardness.