The article discusses the grain morphology of the natural filler from hazelnut and walnut shell flour. It was observed that the geometry of both meals is similar to each other and resembles uneven balls in shape. The heterogeneity and well-developed outer surface of the flour grains allow for filling the voids with the polymer matrix. The analysis of the surface of the SEM images allowed to observe the presence of natural filler flour grains in the entire volume of the produced polymer composites, uneven distribution and small agglomerates, as well as the presence of voids, distributed in the matrix and in the matrix/filler interface. As a result of the visual evaluation of the activity of microorganisms (mycelium) on the surface of the produced polymer composite materials PP/hazelnut and walnut shell flour with a different % share, different fraction, it was found that the best fungistatic effect was shown by the samples marked with the symbol hazelnut at the fraction 315–443 µm. The least fungistatic material was found to be the samples with walnut shell meal filler at the fraction 315–443 µm (F2 and F4), on which the microorganisms achieved significant growth (more than 50% of the test area). The highest value of contact angle was obtained for samples with hazelnut filler fraction 315–443 (C2 and C4), which also confirms its best fungistatic effect.

Purpose: The aim of the article is to present the thermal, electrical and mechanical properties of the produced polymer composites with a filler in the form of charcoal powder. Design/methodology/approach: The tests were carried out on samples of pure polypropylene (PP) and polymer composites, the matrix of which is polypropylene (PP), and the filler was charcoal powder with a volume fraction of 10%, 20%, 30%, 40% and 50%. The tested polymer composites in the form of granules were produced by extrusion, and then standardised test profiles were made by injection moulding. Findings: The hardness of the tested composites was determined by the Shore D method, the grain size distribution of the filler used was determined using the laser method and its thermal stability was tested using the TGA thermogravimetric analysis. The volume and surface resistivity were also determined and the density was determined. It was found that the charcoal powder used as a filler is characterised by high thermal stability – up to 600°C – and with an increase in its volume share in the polymer matrix, the hardness and density of the produced composites increases. Practical implications: The tested composites can be used as structural composites for complex elements requiring high hardness and strength. Originality/value: The research results indicate the possibility of using charcoal as a filler in polymer matrix, which, due to its low production cost, may be an alternative to expensive carbon fillers.

In this work the effect of Mg addition on structure as well as kinetics of crystallisation of Zn-Al-Cu cast alloy was presented. To the zinc alloy was added 0.1% mass of Mg. The alloy was cast into a metal mould. Thermo-derivative analysis was performed using the UMSA platform (Universal Metallurgical Simulator and Analyzer). The investigated alloys were freely cooled down with a rate of 0.1°C s-1. For the structure analysis were used results obtained using light microscopy, scanning and transmission electron microscopy.

This paper presents the influence of casting method and anodic treatment parameters on thickness and structure of an anodic layer formed on aluminium alloys. As test materials was used the aluminium alloy AlSi9Cu3, which was adopted to the casting process and anodic treatment. In this paper are presented the wear test results and metallographic examination, as well as hardness of non-anodised and anodised alloys subjected to anodising process. The investigations were performed using light and electron microscopy (AFM) for the microstructure determination. The morphology and size of the layer was also possible to determine. The anodising conditions for surface hardening and its influence on properties was analysed. The structure of the surface laser tray changes in a way, that there is a different thickness of the produced layer. The aluminium samples were examined in terms of metallography using the optical microscope with different image techniques as well as light microscope. Improving the anodization technology with appliance of different anodising conditions. Some other investigation should be performed in the future, but the knowledge found in this research concerning the proper process parameters for each type of alloy shows an interesting investigation direction. The combination of metallographic investigation for cast aluminium alloys – including electron microscope investigation – and anodising parameters makes the investigation very attractive for automobile industry, aviation industry, and others, where aluminium alloys plays an important role.

Purpose: The aim of this paper is to present a modern manufacturing method of production and compare the thermal, mechanical, properties of composite materials with aluminium alloy matrix reinforced by Al2O3 particles. Design/methodology/approach: The material for investigation was manufactured by the method of powder metallurgy (consolidation, pressing, hot concurrent extrusion of powder mixtures of aluminium EN AW-AlCu4Mg1 (A) and ceramic particles Al2O3). The amount of the added powder was in the range of 5 mass.%, 10 mass.% and 15 mass.%. Findings: The received results concerning the enhancement of hardness, which show the possibility of obtaining the MMC composite materials with required microstructure, influencing the properties of the new elaborated composite materials components. Concerning the thermal properties, especially the linear thermal expansion coefficient was measured, as well as the dilatometric change of the sample length was analysed. Practical implications: Concerning practical implications it can be stated that the tested composite materials can be applied among others in the transportation industry, but it requires additional research. Originality/value: The received results show the possibility of obtaining new composite materials with controlled and required microstructure with possible practical implications.