In the paper, results of impact bending tests of a high-manganese steel of X30MnAlSi26-4-3 grade are presented. The tests were carried out using a flywheel machine, suitable for dynamic tensile tests and impact bending tests in the range of linear velocity of the forcing element from 5 ÷ 40 m/s. The obtained test results were compared with the results of impact resistance of the studied steel determined using Charpy machine. Structural investigations were carried out using light microscope and scanning transmission electron microscopy. Creating a mechanical twins at different strain rates was analyzed. The surfaces of fractures formed in the break point during bending tests were analyzed, and they indicate a presence of mixed transcrystalline fractures with a predominance of plastic fractures. Substructure studies revealed the presence of mechanical twinning induced in a high strain rate for the X30MnAlSi26-4-3 steel.

The results of the microstructure and hardness investigations of the Cu-0.8Cr alloy after application of severe plastic deformation (SPD) implemented by rolling with the cyclic movement of rolls (RCMR) are presented in this paper. Performed substructure investigations showed that using the RCMR method can refine the microstructure of Cu-0.8Cr alloy to the ultrafine scale. The structure of the Cu-0.8Cr alloy was analyzed using light microscope (LM) and scanning transmission electron microscope (STEM). The quantitative studies of the substructure was performed with "MET-ILO" software, on the basis of images acquired on STEM microscope.

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The change of matrix and usage of the aluminum alloys designed for the metal forming in making the composite suspension allows to extend the processing possibility of this type of materials. The possibility of the metal forming of the composites obtained by mechanical mixing will extend the range of composite materials usage. Applying of the metal forming e.g. matrix forging, embossing, pressing or rolling, will allow to remove the incoherence of the structure created while casting and removing casting failures. In order to avoid the appearance of the casting failures the homogenization conditions need to be changed. Inserting the particles into the matrix influences on the shortening of the composite solidification. The type of the applied particles influenced the sedimentation process and reinforcement agglomeration in the structure of the composite. Opposite to the composites reinforced with one-phase particles applying the fasess mixture (glassy carbon and silicon carbide) triggered significant limitation in the segregation process while casting solidification. Inserting the particles into the AW-AlCu2SiMn matrix lowers the mechanical properties tension and impact value strength. The most beneficial mechanical properties were gained in case of heterofasess composites reinforced with the particle mixture of SiC and glass carbon. The chemical composition of the matrix material (AW-AlCu2SiMn) allows to increase additionally mechanical characteristics by the precipitation hardening reached through heat casting forming.