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This paper presents the results of investigations on microstructure changes after the long-term impact of temperature. The microstructure investigations were carried out by light microscopy and scanning electron microscopy. The qualitative and quantitative identification of the existing precipitates was carried out using X-ray phase composition analysis. The effect of elevated temperature on precipitation processes of test material were described. The obtained results of investigations form part of the material characteristics of new-generation alloys, which can be indirectly associated with the stability of functional properties under the simultaneous effect of high temperature and stress.

The presented investigation results were carried out on two binary aluminium-magnesium alloys. The article focuses on the influence of heat treatment conditions on the precipitation response of AlMg3 and AlMg5 aluminium alloy, microstructure evolution and strength of the alloys. The microstructure variation was analysed using a scanning electron microscope and an optical microscope in order to characterise the microstructure in a heat treated condition. Tensile tests and hardness measurements were carried out to investigate the effect of heat treatment on the mechanical properties.

In this paper is presented the structure of the cast magnesium alloys as cast state and after heat treatment cooled with different cooling rate, depending on the cooling medium (furnace, water, air). For investigations samples in shape of 250x150x25 mm plates were used. The structure have been study in the light microscope, scanning electron microscope equipped with an electron back scattering facility. The effects of the addition of Al on the microstructure were also studied. In the analysed alloys a structure of α solid solution and fragile phase β(Mg17Al12) occurred mainly on grain borders as well as eutectic and phase with Mn, Fe and Si. Investigation are carried out for the reason of chemical composition influence and precipitation processes influence to the structure and mechanical properties of the magnesium cast alloys with different chemical composition in as cast alloys and after heat treatment.

The purpose of the article is to present the results of comparative quantitative analysis of selected materials and manufacturing technologies, to indicate their development outlooks and to present its application opportunities in the automotive industry. Concerning of the demand from the automotive sector for components and parts made of cast aluminum alloys, the development expectations of their effective manufacturing technology meeting the expected product properties, including surface laser treatment as well as physical and chemical vapour deposition, were evaluated to be very high.

The article describes the investigation of the effect of electrospinning process parameters wherein the distance between the electrodes was variable, the voltage and the flow rate of the polymer solution was constant for the obtained polymer nanofibers from the solution of PVP/EtOH with concentration of 10% by weight. The morphology of produced nanofibers was examined using a scanning electron microscope (SEM). Based on the SEM images a series of measurements of the nanofibers diameters for each sample were executed and then the results were averaged. The research shows that reducing the distance between the electrodes has a significant impact on the diameter of the PVP nanofibers.

The present study was initiated to investigate the influence of an ECAP die on the microstructure evolution and properties of commercial Al-Mg aluminum alloy in as-cast state. To characterize microstructural features an optical microscope was used. The properties of the as processed and initial state material were evaluated based on the hardness measurements. It was found that the applied ECAP die has the meaningful influence on the microstructure as well as the properties of the material.