Explore the vast range of titles available.

Additive manufacturing is a key component of the fourth industrial revolution (IR4.0) that has received increased attention over the last three decades. Metal additive manufacturing is broadly classified into two types: melting-based additive manufacturing and solid-state additive manufacturing. Friction stir additive manufacturing (FSAM) is a subset of solid-state additive manufacturing that produces big area multi-layered components through plate addition fashion using the friction stir welding (FSW) concept. Because of the solid-state process in nature, the part produced has equiaxed grain structure, which leads to better mechanical properties with less residual stresses and solidification defects when compared to existing melting-based additive manufacturing processes. The current review article intends to highlight the working principle and previous research conducted by various research groups using FSAM as an emerging material synthesizing technique. The summary of affecting process parameters and defects claimed for different research materials is discussed in detail based on open access experimental data. Mechanical properties such as microhardness and tensile strength, as well as microstructural properties such as grain refinement and morphology, are summarized in comparison to the base material. Furthermore, the viability and potential application of FSAM, as well as its current academic research status with technology readiness level and future recommendations are discussed meticulously.

Nowadays, the use of metal processing additive technologies is a rapidly growing field in the manufacturing industry. These technologies, such as metal 3D printing (also known as additive manufacturing) and laser cladding, allow for the production of complex geometries and intricate designs that would be impossible with traditional manufacturing methods. They also offer the ability to create parts with customized properties, such as improved strength, wear resistance, and corrosion resistance. In other words, these technologies have the potential to revolutionize the way we design and produce products, reducing costs and increasing efficiency to improve product quality and functionality. One of the significant advantages of these metal processing additive technologies is a reduction in waste and environmental impact. However, there are also some challenges associated with these technologies. One of the main challenges is the cost of equipment and materials, which can be prohibitively expensive for small businesses and individuals. Additionally, the quality of parts produced with these technologies can be affected by factors such as printing speed, temperature, and post-processing methods. This review article aims to contribute to a deep understanding of the processing, properties, and applications of ferrous and non-ferrous alloys in the context of SLM to assist readers in obtaining high-quality AM components. Simultaneously, it emphasizes the importance of further research, optimization, and cost-effective approaches to promote the broader adoption of SLM technology in the industry.

With the development of society, every year there are increasing demands in the automotive industry on cost savings, environmental safety, reduction of raw material consumption, performance improvement, material life cycle and recycling of components. In this review, emphasis is given on ferrous and non-ferrous alloys, which are used as components, where both groups can be treated by deep cryogenic treatment (DCT). DCT has shown to increase hardness, tensile strength and wear resistance, reduce density of defects in crystal structure, improve toughness and corrosion resistance. Though, some researchers also reported results that showed no change in material properties, or even deterioration of material properties, when subjected to DCT. This additionally points out to lack of consistency and reliability of the DCT process, which is needed for its successful incorporation in automotive applications. However, to prove with certainty the resulting outcome on the material properties and knowledge about the reasons for the variation of this effect on metallic materials, further approach and testing with different variables should be conducted in the future. This review provides a synopsis of different approaches of DCT on different materials for automotive applications in order to indicate effects on the material performance during DCT.

The shape memory effect of steel (i.e., Fe-Mn-Si alloys) enables the tensile strengthening of concrete against tensile stress and unexpected structural vibrations. For practical application, the corrosion resistance of shape-memorable Fe-based steel should be verified. In this study, the corrosion resistance of an Fe-based (Fe-16Mn-5Si-4Ni-5Cr-0.3C-1Ti) shape memory alloy (FSMA), a promising candidate for concrete reinforcement, was investigated by comparing it with general carbon steel (S400). The corrosion resistance of FSMA and S400 inserted in a cement mortar was evaluated using electrochemical methods. FSMA has a more stable passive oxide layer in aqueous solutions with various pH values. Thus, the corrosion resistance of the FSMA sample was much higher than that of the S400 carbon steel, which has a passivation layer in strongly alkaline solution. This stable oxide layer reduced the sensitivity of the corrosion resistance of FSMA to changes in the pH, compared to S400. Furthermore, owing to the stable passive oxide layer, FSMA exhibited a higher corrosion resistance in concrete and a lower decrease in corrosion resistance because of the neutralization of concrete. Therefore, FSMA is a promising candidate for providing reinforcement and reparability, resulting in stable and durable concrete.

The features of the production of welded joints from non-ferrous alloys are considered. The disadvantages of the used capacitor welding methods are described. To reduce the possibility of intermetallic compounds, it is proposed to use high-voltage capacitor welding with induction-dynamic drive (HVCW with IDD) on super-rigid modes of action. The technological scheme methods of HVCW with IDD are given, the physical nature of the impulse process is described. The results of comparative analysis of the waste of thermal energy depending on the technological method and roughness of the welded surfaces, as well as the ratio of thermal and mechanical energies for each method of HVCW with IDD are given.

As industrial development drives the increasing demand for steel, accurate estimation of the material’s fatigue strength has become crucial. Fatigue strength, a critical mechanical property of steel, is a primary factor in component failure within engineering applications. Traditional fatigue testing is both costly and time-consuming, and fatigue failure can lead to severe consequences. Therefore, the need to develop faster and more efficient methods for predicting fatigue strength is evident. In this paper, a fatigue strength dataset was established, incorporating data on material element composition, physical properties, and mechanical performance parameters that influence fatigue strength. A machine learning regression model was then applied to facilitate rapid and efficient fatigue strength prediction of ferrous alloys. Twenty characteristic parameters, selected for their practical relevance in engineering applications, were used as input variables, with fatigue strength as the output. Multiple algorithms were trained on the dataset, and a deep learning regression model was employed for the prediction of fatigue strength. The performance of the models was evaluated using metrics such as MAE, RMSE, R2, and MAPE. The results demonstrated the superiority of the proposed models and the effectiveness of the applied methodologies.

The paper presents changes in the production volume of castings made of non-ferrous alloys on the background of changes in total production of casting over the 2000-2019 period, both on a global scale and in Poland. It was found that the dynamics of increase in the production volume of castings made of non-ferrous alloys was distinctly greater than the dynamics of increase in the total production volume of castings over the considered period of time. Insofar as the share of production of the non-ferrous castings in the total production of castings was less than 16% during the first two years of the considered period, it reached the level of 20% in the last four years analysed. This share, when it comes to Poland, increased even to the greater degree; it grew from about 10% of domestic production of castings to over 33% within the regarded 2000-2019 period. The greatest average annual growth rate of production, both on a global scale and in Poland, was recorded for aluminium alloys as compared with other basic non-ferrous alloys. This growth rate for all the world was 4.08%, and for Poland 10.6% over the 2000-2019 period. The value of the average annual growth rate of the production of aluminium castings in Poland was close to the results achieved by China (12%), India (10.3%) and the South Korea (15.4%) over the same period of time. In 2019, the total production of castings in the world was equal to about 109 million tonnes, including over 21 million tonnes of castings made of non-ferrous alloys. The corresponding data with respect to Poland are about 1 million tonnes and about 350 thousand tonnes, respectively. In the same year, the production of castings made of aluminium alloys was equal to about 17.2 million tonnes in the world, and about 340 thousand tonnes in Poland.

The final session of the meeting consisted of a discussion panel to propose future directions for research in the field of hydrogen embrittlement and the potential impact of this research on public policy. This article is part of the themed issue ‘The challenges of hydrogen and metals’.

Titanium alloys are advanced lightweight materials, indispensable for many critical applications 1 , 2 . The mainstay of the titanium industry is the α–β titanium alloys, which are formulated through alloying additions that stabilize the α and β phases 3 – 5 . Our work focuses on harnessing two of the most powerful stabilizing elements and strengtheners for α–β titanium alloys, oxygen and iron 1 – 5 , which are readily abundant. However, the embrittling effect of oxygen 6 , 7 , described colloquially as ‘the kryptonite to titanium’ 8 , and the microsegregation of iron 9 have hindered their combination for the development of strong and ductile α–β titanium–oxygen–iron alloys. Here we integrate alloy design with additive manufacturing (AM) process design to demonstrate a series of titanium–oxygen–iron compositions that exhibit outstanding tensile properties. We explain the atomic-scale origins of these properties using various characterization techniques. The abundance of oxygen and iron and the process simplicity for net-shape or near-net-shape manufacturing by AM make these α–β titanium–oxygen–iron alloys attractive for a diverse range of applications. Furthermore, they offer promise for industrial-scale use of off-grade sponge titanium or sponge titanium–oxygen–iron 10 , 11 , an industrial waste product at present. The economic and environmental potential to reduce the carbon footprint of the energy-intensive sponge titanium production 12 is substantial. Combining alloy design with additive manufacturing process design creates α–β titanium–oxygen–iron alloys that are both strong and ductile, with the potential to revitalize off-grade sponge titanium and thereby reduce the carbon footprint of the titanium industry.

18% Ni-Co-Mo-Ti ferrous base alloys are special materials, widely used in the industry of isotopic enrichment after specific annealing and aging thermal treatment. The desirable high mechanical properties can then be attained by adequate aging heat treatment, answering the structural materials specifications required by defense applications in aerospace and nuclear engineering. For instance, the isotopic enrichment, in rocket engine envelope application, when associated with high temperature and chemical residues like acidic solutions, can induce corrosion and hydrogen embrittlement in martensitic microstructure. In order to limit these corrosion and hydrogen embrittlement phenomena, adherent and protective layers of iron oxides can be grown on the material’s surface by performing aging treatment in an adequate atmosphere. Due to its application in strategic areas, the characterization of these oxide layers in maraging steels is of importance as well as the understanding of their growth kinetics. For this purpose, several techniques, such as optical microscopy (OM), scanning electron microscopy (SEM), glow discharge optical emission spectroscopy (GDOES), microabrasive wear testing, hardness, grazing incidence X-ray diffraction (GIXRD), and X-ray photoelectron spectroscopy (XPS), have been performed for chemical and structural characterization of the oxide films formed after vapor exposed thermal aging at 510℃. The oxide layer consists of two sub-layers composed by magnetite ( Fe 3 O 4 ) and an external layer of hematite ( Fe 2 O 3 ). A thick interface between the oxide layer and the bulk is enriched in Ti and Mo, whereas the analyses of deep bulk material show an enriched area with Ni and Co.