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There is a long process to transform bauxite, a critical raw material, into a substance with the required properties of cast aluminum alloys for use in electro automotive parts. Thanks to its unique properties, aluminum has become the material of choice for clean technology manufacturers in applications such as use in the automotive industry, renewable energy, batteries, electrical systems, resource-saving packaging, energy efficient buildings and clean mobility. Restructuring of the economy, the oil crisis, air pollution and global warming are some of the factors that have moved the automotive industry towards electrification since the beginning of the 21st century. This paper aims to highlight the required properties of cast aluminum alloys applied to the production of electro automotive parts, such as their mechanical and thermophysical properties, dimensional stability, corrosion resistance, electromagnetic compatibility and crashworthiness. Furthermore, this paper discusses which of the cast aluminum–silicon alloys, as well as the heat treatments and casting processes, are most suitable.

The repair of structural elements for the prestressing of reinforced concrete is necessary when existing prestressing wires are damaged or after a certain period of time. The objective of this paper is to describe the methodology for the life assessment of corroded prestressing wires, sampled from prestressed concrete elements after a few decades of use. The aim of the presented research was to determine the real properties of corroded wire in terms of the evaluation of remaining load capacity using the Theory of Critical Distances (TCD). The methodology also includes spatial 3D characterization of corroded surfaces, determination of mechanical properties, and Finite Element Analysis (FEA) of a model of wire with corrosion pits. The final goal of the presented methodology is to enable more efficient evaluation of repair range and options for the elements of mechanical prestressing systems within various structures. The results and conclusions indicate that the developed methodology, based on the interdisciplinary approach and implementation of state-of-the-art methods, has a high applicability potential for both static and fatigue fracture prediction in the case of prestressed wires. The proposed method has a huge potential for simple and fast prediction of the life assessment of engineering structures, particularly for damaged elements with arbitrary geometry features

The results obtained from the work on a concept of a recycling process for NdFeB magnets to recover rare earth elements for remanufacturing similar magnets are presented. This paper investigates the viability of extracting rare earth metals from magnet recycling-derived oxide (MRDO) by means of molten salt electrolysis. The MRDO was produced from spent NdFeB magnets through oxidation in air and subsequently carbothermic reduction under an 80 mbar Ar gas atmosphere. This MRDO contained roughly 33 wt.% Nd and 10 wt.% Pr. The electrochemical reduction process of the MRDO on molybdenum electrodes in NdF3 + LiF and NdF3 + PrF3 + LiF fused salts systems was investigated by cyclic voltammetry and chronoamperometry measurements. The resulting electrolytes and electrodes were examined after potentiostatic deposition by scanning electron microscopy (SEM), inductively coupled plasma optical emission spectroscopy (ICP-OES), and X-ray diffraction (XRD) analysis. The electrodeposited metals appeared to accumulate on the cathode and X-ray diffraction analysis confirmed the formation of metallic Nd and Pr on the working substrate. The suitability of the obtained alloy intended for the remanufacturing of NdFeB magnets was then evaluated.

Correlation among morphological, structural and hardness characteristics of electrodeposited copper coatings is presented in this review paper. Cu coatings were produced applying constant galvanostatic (DC) and pulsating current (PC) regimes on hard silicon (Si(111)) and brass substrates. The parameters of the electrochemical deposition which include the kinds of electrolyte and cathode, the coating thickness and the electrolyte stirring, as well as the parameters defining PC regime, such as the average current density and the current density amplitude, were analyzed. Morphology and structure of Cu coatings were examined by scanning electron microscope (SEM), atomic force microscope (AFM) and by X-ray diffraction (XRD), while hardness was examined by Vickers microindentation. The coatings of Cu on both Si(111) and brass cathodes belong to “soft film (coating) on hard substrate” composite hardness system, and the Chicot–Lesage (C–L) composite hardness model was applied to estimate a hardness of the Cu coatings. Analyzing the examined parameters and regimes of electrodeposition, the critical relative indentation depth (RID)c of 0.14 has been defined by the C–L model. Based on done analyses, it is shown that this RID value, separating a zone where measured hardness corresponds to the coating hardness and a zone where it is necessary to apply the C–L model to determine an absolute hardness of the Cu coatings, has an universal character for the electrolytically produced Cu coatings on Si(111) and brass substrates.

The automotive industry is in the process of transformation from the traditional production of vehicles with engines powered by the combustion of fossil fuels to vehicles powered by electric energy. This revolutionary transformation will generate a growing demand for metallic raw materials that are a crucial part of batteries—nickel and cobalt, among others. Providing enough raw materials for e-mobility in a sustainable way will be a challenge in the years to come. The region of South-Eastern Europe (SEE) and Turkey is relatively rich in lateritic Ni-Co deposits, and this region has the potential to partially replace the import of nickel and cobalt intermediates to the European Union from distant overseas locations. Possibilities for the sustainable sourcing of nickel and cobalt from the SEE region are reviewed in this paper, with an overview of the global demand and production of these metals, lateritic mineral resources of SEE, the current status of production, and the prospective development of nickel and cobalt production in this region.

Data on the strain and stress status of the pipe in the circumferential direction are required for various pipe manufacturing procedures (e.g., in the oil business, the process of manufacturing seamless pipes with a conical shaft). The aim of this study is to develop a procedure to determine the strain and stress behavior of Pipe Ring Tensile Specimens (PRTSs) in the hoop direction, as there are a lack of official standardized methods for testing PRTS. This paper discusses the application of the Digital Image Correlation method for testing plastic PRTSs. PRTSs are tested using a specially designed steel tool with two D blocks. A 3D-printed PRTS is placed over two D-shaped mandrels, which are fixed on a tensile tool and tensile testing machine. The strain evolution in the gage length of the specimens is captured using the three-dimensional Digital Image Correlation (3D DIC) method. To check the geometry of the cross-section of the PRTS after fracture, all the specimens are 3D scanned. For the study, six groups of PRTS are analyzed, consisting of three filling percentages (60, 90, and 100%) and two geometry types (Single and Double PRTS). The results show that the type and percentage of filling, as well as the method of printing, affect the material behavior. However, the approach with the DIC system, 3D printer, and scanner shows that they are effective instruments for mapping complete strain fields in PRTS, and thus are effective in characterizing the mechanical properties of pipes.

In this paper, we present the idea and development of a new gold-copper-zinc-germanium (AuCuZnGe) alloy, which is related to the method of production and research of its key properties, so that the new Au alloy could be used for jewelry production and in dental technology. The research design was associated with the determination of appropriate chemical composition, manufacturing technology, and performing the characterization. Melting and casting technologies were used to cast the AuCuZnGe alloy while rolling was used to prepare the cylinders and cutting to make square plates with a = 10 mm and thickness of 1 mm. Such plates were provided for corrosion testing. Observation of the plate′s microstructure was performed with Scanning Electron Microscopy (SEM) equipped by Energy-Dispersive X-ray spectrometry (EDS) and X-ray diffraction (XRD). Corrosion testing involved performing the following measurements: Polarization, the open circuit potentials, and linear polarization resistance. Based on the SEM, EDS, XRD, and results of corrosion testing it can be concluded that the new AuCuZnGe alloy possesses high corrosion stability and can be classified as a high noble alloy.

The automotive industry is in the process of transformation from the traditional production of vehicles with engines powered by the combustion of fossil fuels to vehicles powered by electric energy. This revolutionary transformation will generate a growing demand for metallic raw materials that are a crucial part of batteries—nickel and cobalt, among others. Providing enough raw materials for e-mobility in a sustainable way will be a challenge in the years to come. The region of South-Eastern Europe (SEE) and Turkey is relatively rich in lateritic Ni-Co deposits, and this region has the potential to partially replace the import of nickel and cobalt intermediates to the European Union from distant overseas locations. Possibilities for the sustainable sourcing of nickel and cobalt from the SEE region are reviewed in this paper, with an overview of the global demand and production of these metals, lateritic mineral resources of SEE, the current status of production, and the prospective development of nickel and cobalt production in this region.