3D printing, also known as additive manufacturing (AM), represents a rapidly evolving technological field capable of creating distinctive products with nearly any irregular shape, often unattainable using traditional techniques. Currently, the focus in 3D printing extends beyond polymer and metal structural materials, garnering increased attention towards functional materials. This review conducts an analysis of published data concerning the 3D printing of magnetic materials. The paper provides a concise overview of key AM technologies, encompassing vat photopolymerization, selective laser sintering, binder jetting, fused deposition modeling, direct ink writing, electron beam melting, directed energy deposition and laser powder bed fusion. Additionally, it covers magnetic materials currently utilized in AM, including hard magnetic Nd–Fe–B and Sm–Co alloys, hard and soft magnetic ferrites, and soft magnetic alloys such as permalloys and elect­rical steels. Presently, materials produced through 3D printing exhibit properties that often fall short compared to their counterparts fabricated using conventional methods. However, the distinct advantages of 3D printing, such as the fabrication of intricately shaped individual parts and reduced material wastage, are noteworthy. Efforts are underway to enhance the material properties. In specific instances, such as the application of metal-polymer composites, the magnetic properties of 3D-printed products generally align with those of traditional analogs. The review further delves into the primary fields where 3D printing of magnetic products finds application. Notably, it highlights promising areas, including the production of responsive soft robots with increased freedom of movement and magnets featu­ring optimized topology for generating highly homogeneous magnetic fields. Furthermore, the paper addresses the key challenges associated with 3D printing of magnetic products, offering potential approaches to mitigate them.

In recent years, the mechanical engineering sector has undergone significant changes due to the creation and expanding application of new technologies and materials capable of radically improving the quality of manufactured products, the entire structure and production conditions. Such technologies include additive manufacturing capable of creating products from advanced materials such as continuous reinforced polymer composites. Furthermore, the integration of additive manufacturing with industrial robots offers new opportunities to create spatially reinforced composites with a directed internal structure, obtained by the orderly arrangement of continuous fibres. This review analyzes the currently available technologies for 3D printing spatially reinforced polymer composites with the addition of continuous fibers using industrial robots. The review presents the main advanced companies supplying off-the-shelf commercial systems and presents the successful experience of using these systems in the production of reinforced parts

This study explores an intermetallic orthorhombic titanium alloy produced by incorporating varying copper concentrations ranging from 0 to 6 wt. % through in-situ doping during selective laser melting (SLM) fabrication, coupled with simultaneous substrate preheating. The investigation delves into the influence of copper introduction on grain refinement within the primary B2/β-phase and subsequent alterations in mechanical properties. Through X-ray diffraction analysis and scanning electron microscopy, the microstructure characterized by the presence of the B2/β-phase and orthorhombic phase precipitates was identified. Additionally, the detection of a minor quantity of the α₂-Ti₃Al-phase was noted, with its proportion increasing proportionally with the augmentation of copper content. Differential scanning calorimetry revealed a shift in the phase transformation temperatures towards higher temperatures and a constricted α₂-Ti₃Al + B2/β + Ti₂AlNb region, attributed to the inclusion of copper. The addition of copper, up to 6 wt. %, resulted in the softening and embrittlement of the orthorhombic alloy, forming a fine-grained microstructure with an average grain size of 8.3 μm. Energy dispersive X-ray spectroscopy confirmed the presence of an intermetallic O-phase along the grain boundaries, contributing to a 12 % increase in hardness compared to the orthorhombic alloy without copper after SLM with substrate heating at 850 °C. An alloy containing 4 wt. % copper exhibited superior plastic properties and a tensile strength of 1080 MPa, comparable to the strength of the orthorhombic alloy obtained via SLM followed by hot isostatic pressing.

This study presents the synthesis of (TiZrHfTaNb)C, (TiTaNb)_0.45Hf_0.275Zr_0.275С and (TiTaNb)_0.3Hf_0.35Zr_0.35С single-phase, high-entropy carbides through mechanical alloying and plasma sintering. High-entropy carbides hold promise for applications in jet engine components. We identified optimal mechanical alloying conditions to achieve powder homogeneity and minimize iron fouling. The microstructure, phase, and chemical compositions of the samples were investigated. At 1600 °C, a sample with a face-centered cubic (FCC) lattice and low content of zirconium and hafnium oxides was formed. Elevating the sintering temperature to 2000 °C facilitated oxide dissolution and the formation of single-phase, high-entropy carbides. The microhardness of the samples ranged from 1600 to 2000 HV, while the compressive strength varied between 600 and 800 MPa. Plasma heating tests demonstrated excellent resistance to thermal oxidation for (TiTaNb)_0.3Hf_0.35Zr_0.35С, withstanding temperatures up to 2250 °C.

Selective laser melting (SLM) proves to be a suitable method for fabricating multi-material products, offering heightened performance. The objective of this study is to examine the mechanical properties of the VZh159–CuCr1Zr multi-material system produced through selective laser melting. We conducted tensile and compressive strength tests on these samples, followed by fractography, examination of polished sections, and a comparison of measured mechanical properties with existing data. Our findings are summarized as follows: the phase compositions in the regions of pure alloy denote solid solutions. X-ray diffraction (XRD) patterns of the interface zone reveal peaks corresponding to both alloys. The tensile strength of VZh159–CuCr1Zr multi-material samples, as measured in tensile tests, is σ_u = 430 ± 20 MPa, with a relative elongation of ε = 4.6 ± 0.3 %. Results from compressive strength tests show values of σ_u = 822 ± 23 MPa, and relative compression ε = 42.5 ± 1.5 %. Comparing these values with those of the pure CuCr1Zr alloy, the ultimate tensile strength is approximately 53 % higher (according to available data), while the conditional yield strength is about 80 % higher. Fractography of the VZh159–CuCr1Zr multi-material sample after tensile tests indicates that the interface zone exhibits both more ductile fracture features characteristic of the CuCr1Zr alloy (pits and a lack of a smooth surface) and less ductile features charac­teristic of the VZh159 alloy (microcracks). Examination of the polished section of a VZh159–CuCr1Zr multi-material sample after compressive strength tests reveals that the presence of a more ductile CuCr1Zr alloy in the interface zone contributes to arresting the crack, which propagates at a 45° angle to the direction of load application in the VZh159 alloy region.

The Metal Paste Deposition (MPD) method offers several advantages in producing multi-materials compared to other additive technologies. While there have been studies conducted on multi-material production using this method, they are limited. Hence, a significant objective is to expand the research scope concerning multi-materials produced through the MPD method. This study aimed to examine samples of multi-material systems comprising 316L steel with CoCrFeMnNiW_0.25 and 316L steel with CrMoNbWV obtained from metal paste. The investigation involved forming multi-material samples and analyzing the porosity, microstructure, phase composition, and hardness of the 316L steel metal paste after sintering. The findings lead to several conclusions: when forming multi-material samples of the 316L–CoCrFeMnNiW_0.25 system, there is no necessity to create a transition zone using mixed 316L steel and CoCrFeMnNiW_0.25 powders, as these alloys mix strongly within it. However, in the 316L–CrMoNbWV system, forming a transition zone of mixed powders is necessary to mitigate the effects of uneven shrinkage. Altering the sintering modes for multi-material samples of the 316L–CoCrFeMnNiW_0.25 system is recommended; the temperature should be reduced by 30–45 °C compared to the sintering modes for 316L steel. After sintering the metal paste derived from 316L steel, the resulting sample exhibits large and small spherical pores. To minimize these defects, degassing can be employed. Additionally, reducing porosity can be achieved through hot isostatic pressing post-sintering. The microstructure following the sintering of the metal paste from 316L steel consists of coarse austenite grains with minimal ferrite accumulation at the grain interface.

Manufacturing of multi-material products through layer-by-layer synthesis poses various challenges encompassing process parameter optimization, equipment calibration, and the mitigation of warping and internal stresses within the manufactured parts. The article investigates the feasibility of simulating the selective laser melting (SLM) process for manufacturing multi-material components, exemplified through specimens composed of the VZh159 nickel alloy and CuCr1Zr copper alloy. The study entails numerical simulations of the printing process, which were then validated against real specimens produced through SLM. Each test specimen was vertically divided into three parts: the top and bottom sections consisted of the VZh159 alloy, while the central part was composed of the CuCr1Zr alloy. Simulations involved using identical process parameters as employed in the printing process. Thermal and mechanical analyses for each part of the multi-material specimen were sequentially addressed, transferring the outcomes of the preceding analysis as initial conditions for subsequent calculations. The study concludes that while the obtained simulation results are indicative, they do not precisely capture the deformation observed in the specimens manufactured via the SLM method. The numerical values of deformations derived from simulation results slightly underestimate the actual deformations, attributed to limitations in the chosen calculation algorithms. For future utilization of numerical computer simulation in the SLM manufacturing of multi-material specimens, the study suggests the necessity of implementing a seamless, continuous simulation process without transitions between different parts of the specimen. This entails considering the entire manufacturing process without segregating sections, ensuring a comprehensive account of continuous deformation and stress accumulation throughout fabrication.

In recent years, the development of additive technologies has been one of the priority tasks in the sector. Primarily, additive technologies enable the effective implementation of various design and engineering ideas in high-tech industries, such as the aircraft industry, engine technology, and rocket engineering. The expanded range of standardized materials for additive technologies will facilitate their integration into large-scale production. Of significant interest is the potential use of nitrogen-containing heat-resistant powder alloys to produce complex-shaped aircraft parts using additive technologies. This paper describes the complete process of obtaining samples from powders of alloys with superequilibrium nitrogen content using the selective laser melting (SLM) method. Four different compositions of high-nitrogen steels were obtained through mechanical alloying. Subsequently, the powders of these steels underwent processing using the plasma spheroidization method to be utilized in the SLM process. The SLM method was also employed to produce samples for mechanical tests. Throughout each stage of the process, the powders were thoroughly analyzed. One of the most critical parameters was the nitrogen content in the resulting powders. At each subsequent production stage, its proportion decreased, yet it remained at the superequilibrium content level of 0.13–0.44 wt. %. The mechanical tests confirmed that the alloys fabricated by the SLM method are not inferior in terms of their properties compared to those obtained using classical metallurgical technologies.