Magnesium alloys thanks to their high specific strength have an extensive potential of the use in a number of industrial applications. The most important of them is the automobile industry in particular. Here it is possible to use this group of materials for great numbers of parts from elements in the car interior (steering wheels, seats, etc.), through exterior parts (wheels particularly of sporting models), up to driving (engine blocks) and gearbox mechanisms themselves. But the use of these alloys in the engine structure has its limitations as these parts are highly thermally stressed. But the commonly used magnesium alloys show rather fast decrease of strength properties with growing temperature of stressing them. This work is aimed at studying this properties both of alloys commonly used (of the Mg-Al-Zn, Mn type), and of that ones used in industrial manufacture in a limited extent (Mg-Al-Sr). These thermomechanical properties are further on complemented with the microstructure analysis with the aim of checking the metallurgical interventions (an effect of inoculation). From the studied materials the test castings were made from which the test bars for the tensile test were subsequently prepared. This test took place within the temperature range of 20°C – 300°C. Achieved results are summarized in the concluding part of the contribution.

The aim of this study was to present the results of the examinations of the structure and thermomechanical properties of PA6/NanoBent composite. NanoBent composites composed of minerals from the smectite group (mainly montmorillonite) were used for modification of polyamide 6. PA6 composite with content of 1, 3, 5% of NanoBent was prepared in a Theysohn TSK 75-N twin screw extruder. The samples were prepared using the injection technology by means of a Krauss-Maffei KM65-160 C1 injection molding machine. The samples of composites obtained at different injection temperatures and injection mold temperatures were used for the examinations. Degree of crystallinity was examined using the DSC method whereas the material structure was examined with an optical microscope. DSC studies showed a reduction in the value of the degree of crystallinity with the increasing content of nanofiller in the polymer material. The narrowing of the peak was recorded in the DSC thermograms for nanocomposites with greater percentage of the nanofiller. Dynamical properties of polyamide 6 nanocomposite were also determined in relation to temperature and frequency. The samples were bended at frequencies of 1 Hz and 10 Hz over the temperature range from –100°C to 180°C and the heating rate of 2K/min. A significant increase in storage modulus was observed for PA6 samples with the content of 5% of NanoBent obtained at the injection temperature of 270°C and mold temperature of 70°C. Smaller size of spherulites and arrangement of structural elements in clusters along the line of polymeric material flow in the mold cavity at higher contents of NanoBent were observed during structural examinations of the composites.