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The paper presents results of FEM modelling as well as properties and microstructure of the ultralow-carbon ferritic steel after the unconventional SPD process—DRECE (dual rolls equal channel extrusion). Based on the conducted numerical simulation information about the deformation behaviour of a steel strip during the DRECE process was obtained. The simulation results were experimentally verified. The influence of DRECE process on hardness distribution, fracture behaviour and microstructure evolution of the investigated steel was analysed. The increase of steel strength properties after subsequent deformation passes was confirmed. The microstructural investigations revealed that the processed strips exhibit the dislocation cell microstructure and subgrains with mostly low-angle grain boundaries. The grains after processing had relatively high dislocation density and intense microband formation was observed. It was also proved that this unconventional SPD method fosters high grain refinement.

Silver, silver alloys, and composites with silver matrix are used mainly as electric contacts, circuit-breakers, and slide bearings. Contacts working conditions require as high as possible thermal and electrical conductivity, wear resistance during electric arc work, low susceptibility to tacking, and chemical stability. Unreinforced silver alloys do not meet those expectations, hence increasing interest in metal matrix composites. Reinforcing with ceramic particles improves tribological wear resistance and minimizes formability of silver alloys. At the same time, introduction of ceramic particles decreases thermal and electrical conductivity. In this paper, manufacturing method of silver-based composites reinforced with particles Al2O3, SiC, and glassy carbon was described. Composites were subjected to differential thermal analysis. Furthermore, thermal diffusivity measurements using laser flash method, as well as measurements of linear thermal expansion coefficient using dilatometric method were performed in order to determine heat conductivity of the prepared composites.

In this paper, the heat generated during deformation under the static testing of high-manganese TWIP steel with addition of niobium was determined. The research combined the interaction of heat generated during deformation, mechanical properties, hardness and microstructure. Temperature and strain were measured simultaneously using infrared (IR) thermography and digital image correlation (DIC) method. The average temperature measured at the necked region equals 42°C at the strain rate of 0.001 s−1 and exceeds 100°C at 0.5 s−1. Therefore at large strains, a reduction in stress was observed. The course of the hardness change coincides very well with the strain changes, however, at the strain rate of 0.5 s−1 near to the necking area the hardness equals to 360 HV2, whereas at the lower strain rates it equals to 370 HV2. These changes are connected mainly with increase in temperature to >100°C