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The authors studied the possibility of using the wire arc additive manufacturing (WAAM) technology for creating blanks by gradually depositing layers of three grades of stainless steel using a wire. Metallographic studies, ferromagnetic analysis, tensile and fatigue tests were carried out. It has been established that the chemical composition of the utilized grades of stainless steel has a significant effect on the morphology and degree of development of dendrites formed during the deposition process. The absence of incomplete fusion and other technological defects at the weld bead interface promoted the possibility of using WAAM to create biand tri-metal deposits. The analysis of the fracture surfaces of the samples confirmed the high quality of fusion of various grades of austenitic steels with each other and the uniformity of the deposited metal. The presence of ferromagnetic phases in the samples immediately after the additive process is significantly lower than the calculated values for steel 07Cr25Ni13 and practically reaches the values that are characteristic for this steel after heat treatment. [ABSTRACT FROM AUTHOR]

The mechanical properties of materials 3D-printed by wire arc additive manufacturing (WAAM) are studied. Thermal and vibrational treatment is found to decrease the anisotropy and improve the properties of the materials at low temperatures. This implies that heat treatment of small components and vibration treatment will be expedient in other cases. [ABSTRACT FROM AUTHOR]

The modeling of cutting fluid supply systems for die pressing using a computational fluid dynamics module is considered. The modeling stages are presented to solve the problem of optimizing cutting fluid supply systems in order to analyze the uniform distribution of lubricant over the working surfaces of the die and analyze their temperature fields. The order of construction, initial and boundary conditions, goals, and calculation results are considered. [ABSTRACT FROM AUTHOR]

The mechanical properties of aluminum matrix composites at negative temperatures are assessed experimentally by means of the classification of acoustic emission pulses; attention focuses, in particular, on the ductile–brittle transition temperature. This transition does not occur even at –100°C, and so it is possible to use aluminum matrix composites for suspension components operating in the Arctic and Antarctic. [ABSTRACT FROM AUTHOR]

Abstract—The influence of heat and vibration treatment on the structure and mechanical properties of experimental specimens prepared from an ER70-S6 welding wire by additive electric arc growth is considered. Based on the results of impact strength tests, the cold resistance of the experimental specimens is estimated. Electron microscopy is used to analyze the microstructure of the material and to calculate the grain size. Heat treatment and vibration treatment are shown to significantly increase the cold resistance of the materials produced by electric arc cladding. Replacement of heat treatment operations is possible by introducing the function of vibration treatment of a weld pool into hybrid machining centers. [ABSTRACT FROM AUTHOR]

Currently, additive technologies, in particular, electric arc growth as the most universal and productive, are used to produce individual machine parts. The problem of studying the process of structure formation in alloys during electric arc additive growth to ensure the necessary parameters of the microstructure of a material and its mechanical properties is challenging. 09G2S steel samples for research are fabricated on a developed test bench implementing the technology of 3D printing by electric arc surfacing, microstructural studies on an optical microscope are used, and microhardness measurements are carried out. The features of structure formation in a 09G2S alloy during additive electric arc growth have been determined, and controlled parameters have been identified to ensure the necessary parameters of the structure and, consequently, the mechanical properties of the alloy. The heat input of the surfacing process and the temperature of a thermal cycle are found to play a significant role in the structure formation in the material. The conducted research and established dependences make it possible to control the structural state of 09G2S steel during cladding to ensure the required parameters of its microstructure and mechanical properties. [ABSTRACT FROM AUTHOR]

The article presents the results of experimental studies of the fatigue strength of specimens manufactured by 3D printing out of various metal wires using the technology of wire arc additive manufacturing (WAAM). It is established that the fatigue strength of specimens made of corrosion-resistant 08H18N9 steel is higher than that of specimens made of low-carbon 08G2S steel and АМg5 aluminum alloy. It is shown that the greater fatigue strength of 08H18N9 steel is associated with its high plasticity. Approaches to increasing the plasticity of metals are proposed. [ABSTRACT FROM AUTHOR]

The poor performance of 3D-printed components in extreme conditions is investigated. It is found that macroscopic crystal lattice defects are formed at the boundary between the layers in additive manufacturing and high internal stress develops. That may be regarded as the main factor impairing the mechanical properties of 3D-printed metal. Additional heat treatment is required to improve the mechanical properties. [ABSTRACT FROM AUTHOR]

The structural changes in 09G2S steel produced by 3D printing (electric arc surfacing) under fatigue loads are studied over a broad range of temperature and cyclic stress variation. The kinetics of crack nucleation and growth in the steel is investigated. A neural network model is proposed to assess the remaining life, taking account of the microstructural evolution of the 09G2S steel in the tests. [ABSTRACT FROM AUTHOR]

The cold strength and mechanical properties of AMg5 aluminum alloy produced by additive electric arc surfacing are considered. The mechanical properties of the 3D-printed alloy are worse than those of the rolled alloy. Quantum-mechanical calculations show that alloying with nanoparticles optimally improves the mechanical properties of aluminum alloys. Alloying with zirconium and tantalum or with titanium intermetallides is particularly effective. [ABSTRACT FROM AUTHOR]

A methodology has been developed for the nanomodification of carbon steel in 3D printing by electric-arc surfacing. Such nanomodification improves the mechanical properties and cold resistance. The alloying elements are selected on the basis of quantum-mechanical calculations and optimization of the nanoparticle content in the melt by neural network modeling. [ABSTRACT FROM AUTHOR]

Structural alloys produced by an additive arc process are tested. Impact-flexure tests with subsequent fractographic analysis show that 09Г2С steel switches from ductile to brittle failure below −60°C, but there is no such change for 07Х25Н13 steel and AMg5 alloy down to −150°C. Assessment of the metal failure by means of fractal analysis and a neural network is proposed. [ABSTRACT FROM AUTHOR]

A smart system for predicting the fatigue strength of metals over a broad temperature range is developed on the basis of a specially trained neural network. The system can predict the number of loading cycles to failure and also the onset of fatigue-crack formation and the rate of crack growth in different test conditions, including low temperatures. [ABSTRACT FROM AUTHOR]

The cold strength and low-temperature failure of 3D-printed 08Г2С and 07Х25Н13 steels are considered. Specifically, the metals are produced by electric arc surfacing. With decrease in temperature, the impact strength of the steels falls. The impact strength is higher for samples cut along the surfacing direction than for those cut in the transverse direction. The brittle component predominates in the fracture of 08Г2С steel below −40°C. By contrast, the ductile component is seen in the fracture of 07Х25Н13 steel at any temperature. A relationship is established between the fractal dimensionality of the fracture surface and the quantity of ductile component. [ABSTRACT FROM AUTHOR]

A smart system is developed for predicting the properties of metals. A specially trained neural network generates a model of a dynamic system for the synthesis of new materials, with 3D printing. The system is able to predict time series analogous to the evolution of fractal characteristics of acoustic emissions associated with solidification. [ABSTRACT FROM AUTHOR]

The strength and low-temperature stability of 09Mn2Si steel are investigated. The mechanical properties of samples obtained by 3D printing (electric arc surfacing) in CNC machine tools are close to those of samples obtained from rolled sheet. In fact, the strength and yield point after 3D printing are superior. However, the low-temperature stability of 09Mn2Si steel samples obtained by electric arc surfacing is worse than for samples from rolled sheet. The results show that electric arc surfacing is promising for the 3D printing of cold-resistant materials in CNC machine tools. [ABSTRACT FROM AUTHOR]

Diagnostics and dynamic optimization of the electrical arc in 3D printing on a CNC machine are considered. The applicability of nonlinear dynamic methods in assessing the stability of 3D printing is assessed. Artificial neural networks are used in classifying and optimizing the process parameters. [ABSTRACT FROM AUTHOR]

Chip formation in machining is investigated. A relation is established between the type of chip, the type of crystal lattice, and the number of slip systems. A neural-network model of chip formation permits prediction of the type of chip. A smart control system for chip formation is proposed. [ABSTRACT FROM AUTHOR]

Impact flexure and indentation of metals is considered. A test bench for failure assessment is developed, for the example of steel 45 at low temperatures. In this method, acoustic emission pulses are classified; an artificial neural network is employed. The fractographic data for impact flexure correlate well with the results of pulse recognition. [ABSTRACT FROM AUTHOR]

The potential benefits of switching industrial enterprises to digital production with integration of the physical and computational processes in a unified informational space are considered. An intelligent device based on neuromorphic computations is proposed for the adaptive control of cutting. The current state of CNC machine tools is assessed. [ABSTRACT FROM AUTHOR]

A system has been developed for 3D printing by means of arc welding in CNC machines. Modules for high-speed computation and for the training of neural networks (with feedback) may be connected to this 3D printing system so as to optimize the welding process and improve product quality. A digital twin expands the capabilities of CAM systems in preparing control programs and equipment for CNC machines. [ABSTRACT FROM AUTHOR]

A digital model of a cutting tool produced by neural-network modeling is considered. By means of this model, the composition and structure of a wear-resistant coating may be optimized. The machining conditions that ensure maximum wear resistance of the tool may also be identified. [ABSTRACT FROM AUTHOR]

Neural-network models used in the development of digital twins for production equipment are considered. Such a model of the dynamic stability of cutting is assessed. A spectrogram showing the vibrational amplitude and frequency of the elastic system in a CNC machine tool is presented. The fractional dimensionality of the corresponding attractors is determined. [ABSTRACT FROM AUTHOR]

Multistage modular design of machine-tool equipment as cyberphysical systems on the basis of artificial intelligence and cloud technology is proposed. [ABSTRACT FROM AUTHOR]

The change in mechanical properties due to low temperatures and the associated damage are studied for various metals. Cracks in austenitic steel are found to be due to large carbides, nitrides, and carbonitrides. The time for a brittle crack to propagate in metal depends on the grain size, the elastic modulus and the density. [ABSTRACT FROM AUTHOR]

Abstract: An approach to the design of routes for driverless vehicles in the Arctic and Far North is discussed. The proposed approach employs artificial intelligence and drones. [ABSTRACT FROM AUTHOR]

The fatigue failure of steel 20 at low temperatures is considered. Strain hardening of the surface layers is found to occur in adiabatic conditions at low temperatures. That increases the fatigue strength. Fatigue cracks form and grow along the grain boundaries. The influence of impurities on the fatigue failure of low-carbon steel is studied. [ABSTRACT FROM AUTHOR]

The failure of materials at low temperatures is studied. The acoustic signals emitted in the extension of steel 45 at low temperature are analyzed. In this conditions, the yield point and strength increase, while the relative elongation declines. [ABSTRACT FROM AUTHOR]

By multifractal parameterization of the contact surfaces of the tool and the supporting surface of the chip in the cutting process, the relation of the fractal dimensionality with the tool's wear rate and the informational entropy is established. In addition, the nonlinear dependence of the tool life on the cutting speed is found. A diagnostic system for monitoring the dynamic stability of the cutting system and the tool wear is proposed. [ABSTRACT FROM AUTHOR]

A drone-based autonomous robot diagnostic system for gas and oil pipelines in the Arctic and Far North has been developed. [ABSTRACT FROM AUTHOR]