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Mechanical properties of widely applicable thin nanocrystalline films have been a sub- ject of interest for some time due to deviation of their properties from the properties of bulk and micro sized grain materials. The deformation mechanisms in these materials are altered by restricted size of the material and high ratio of surface and grain boundary areas. Recent advances in transmission electron microscopy (TEM) allow direct obser- vations of the deformation mechanisms during nanoindentation or tensile deformation of the specimen. Thin Al films prepared by DC magnetron sputtering were deformed in situ in TEM and bright field TEM. High resolution TEM and automated crystallographic orientation mapping (ASTAR) were implemented to observe the ongoing deformation mechanisms. Molecular dynamic simulation designed to approach the conditions of per- formed experiment were used to visualize the deformation mechanisms on atomic scale and the reliability of both methods was discussed. 1

Thermal stability of Al-Fe-Mn-Si alloys prepared by twin roll casting accom- panied by intensive cooling and plastic deformation was studied. The goal of the study is to map processes occurring during a model homogenizaton annealing of individual alloys which differ by the ratio of alloying elements. Model in-situ an- nealing in the transmission electron microscope and resistometry measurements with linear heating were used for identification of occurring processes. Another goal is to determine the crystalographic structures of primary and secondary pha- ses present in the alloys. Results show that the concentration of alloying elements has a significant influence on transformation temperatures of primary phases as well as the structure of primary and secondary phases. 1

New technologies of components assembling in car and aircraft industries and requests on improved mechanical and corrosion properties of metallic materials in the packing industry activate the utilization of highly innovative and unconventional manufacturing processes. There are only a limited number of processing, that retain the original material thickness and in an appropriate manner modify material properties. These are different types of annealing, severe plastic deformation methods or combination of both. In recent years constrained groove pressing (CGP) was devoloped with this method the grain size can be reduced from tens of micrometers to sub-micrometers. The present work is focused on a study of evolution of microstructure and mechanical properties of two alloys based on EN AW 3003 after CGP deformation and subsequent annealing.

Aluminium alloys of the 6### series are widely used in the industry. To achieve the optimal properties, the as-cast alloy must by treated by several steps. The first treating step is the homogenization annealing of the as-cast alloy. During homogenization dissolution of eutectic phases occurs and distribution of impurity elements in the alloy is more uniform. It requires a high annealing temperature near the melting point of the alloy. One of the method that allows direct observation of the microstructure during homogenization is in-situ electron microscopy. Specimens from EN AW 6082 alloy were annealed in several model homogenization regimes and in-situ monitored by electron microscopy. Observed processes were compared with the results of resistivity measurements. EDS measurements were taken at the beginning and at the end of the homogenization process.

Heat exchangers in automotive industry are often manufactured from aluminum-based alloy AW 3003. In recent time, the aim to reduce the weight of the cars leads to thickening of the foils, which are used for manufacturing of the heat exchangers. In order to fulfill all requirements on mechanical properties of the exchanger, new materials and thermo-mechanical treatments have to be found. Modified alloy AW 3003 with addition of zirconium seems to be perspective. Zirconium forms metastable precipitates Al3Zr, which pin moving grain boundaries and shift recrystallization to higher temperatures. The most effective heat treatment, which leads to precipitation of these particles, seems to be a two-step annealing at temperatures 250 řC and 450 řC with slow heating rate. The precipitates formed were of diameter 10 nm.

As a preparation for the study of dispersed particles in the aluminium alloys the ALCHEMI method was tested on a simple model material. This method combines the X-ray spectrum analysis and the dynamic diffraction to provide the information on site occupancies. The site preference of Cr in the Fe3Al and FeAl materials was studied. Measured variation of the X-ray yields with the orientation near the Bragg position was fitted by the calculated curves. We found that 70 resp. 80 % of Cr occupy the Al sublattice.