The results of flyer acceleration up to the velocity of 10 km/s at the Angara-5-1 facility at the current of 5 MA by the magnetic field pressure are presented. 1D and 2D simulation of aluminum flyer acceleration is performed. The simulation results agree with each other and with the experimental data.

A new low-activation austenitic steel with a modified composition and high austenite stability is proposed. The features of its microstructure after solution treatment (ST) and cold rolling (CR) are studied. The mechanical properties and features of the fracture behavior of this steel under tensile tests in the temperature range of 20–750 °C are discussed. After ST, an austenitic structure with stacking faults and dispersed carbide particles of the MC and M23C6 types is observed in the steel. After CR, the grains are refined, and the average grain size decreases from 41.4 µm (after ST) to 33.9 µm. High-density microtwin packets form in the material, and the dislocation density increases relative to that after ST. As the test temperature increases from 20 to 750 °C, the yield strength of the steel decreases by approximately two times, from ≈300 to 150 MPa (for ST) and from ≈700 to 370 MPa (for CR). In the studied temperature range, the steel demonstrates up to 2.6 times higher values of elongation to failure, ≈40–80% (for ST) and ≈13–27% (for CR), compared to steels of similar compositions and lower manganese content. Mechanical twinning contributes to the high steel ductility up to 300 °C. Signs of discontinuous flow in the tensile curves after ST in the temperature range of 500–600 °C and a decrease in the elongation to failure in the close temperature range indicate dynamic strain aging (DSA). Steel fracture after tension at all test temperatures mainly occurs via a ductile dimple transcrystalline mechanism with elements of ductile intercrystalline fracture. It is shown that cracks nucleate on clusters of dispersed second-phase particles. The mechanisms of plastic deformation, fracture, and strengthening of the proposed modified low-activation austenitic steel are discussed.

The article presents the results of developing the single-frequency pulsed Nd : YAG laser system at the 660 nm wavelength with a pulse duration of 50 ns and repetition rate of 1-10 Hz, operating in a Q-switched mode with injection of external radiation. Various schemes of forming a feedback system for controlling the spectral composition of the laser system are considered. It is shown that the method of locking the master oscillator frequency to the mode of the pulsed laser cavity has a number of advantages over the method of stabilizing the cavity length. Keywords: Solid-state laser, Q-switching modulation, injection of radiation.

Представлены результаты разработки одночастотной импульсной лазерной системы Nd : YAG на длине волны 660 nm с длительностью импульсов 50 ns и частотой повторения импульсов 1-10 Hz, работающей в режиме модулированной добротности с инжекцией внешнего излучения. Рассмотрены различные схемы формирования системы обратной связи для управления спектральным составом лазерной системы. Показано, что метод привязки частоты задающего генератора к моде резонатора импульсного лазера обладает преимуществами по сравнению с методом стабилизации длины резонатора. Ключевые слова: твердотельный лазер, модуляция добротности, инжекция излучения.

Optical generation of kilo-tesla scale magnetic fields enables prospective technologies and fundamental studies with unprecedentedly high magnetic field energy density. A question is the optimal configuration of proposed setups, where plenty of physical phenomena accompany the generation and complicate both theoretical studies and experimental realizations. Short laser drivers seem more suitable in many applications, though the process is tangled by an intrinsic transient nature. In this work, an artificial neural network is engaged for unravelling main features of the magnetic field excited with a picosecond laser pulse. The trained neural network acquires an ability to read the magnetic field values from experimental data, extremely facilitating interpretation of the experimental results. The conclusion is that the short sub-picosecond laser pulse may generate a quasi-stationary magnetic field structure living on a hundred picosecond time scale, when the induced current forms a closed circuit.

When processing experimental data with systems such as velocity interferometer system for any reflector (VISAR), periodic measurement uncertainty arises. The appearance of its uncertainty is investigated and computer modeling of signal processing with random noise is carried out. Analytical dependences of the error value on the signal-to-noise ratio and signal phase are obtained. Methods of reducing this error are considered.

Progress in improving the accuracy of metal-cutting machines is inextricably linked and driven by deeper knowledge gained through the study of thermal processes and effects occurring in machines, which can be used to manage them. This led to the dominance of temperature errors in the balance of machine accuracy, the share of which changed from 20-30% to 70% during the period from 1950 to 2020, which is determined by the absolute value of the achievable machine accuracy. Types and forms of compensation methods were formed (1990-2020), which were based on the use of linear and nonlinear regression or correlation methods. Performing experiments can establish the functional relationship between the measured temperature in the machine nodes and the amount of displacement. With good repeatability and stable reproducibility of the result, an equation expresses this functional relationship. Applying this equation to a program, a control device compensates the thermal deformations. However, in all cases, it is necessary to determine the number and location of temperature measurements on the machine, determining the compensation accuracy. The proposed sensorless model is based on a thermal behavior model and does not require temperature measurements. A method is presented and justified for estimating the number of temperature measurement locations based on thermophysical analysis by applying the finite element method in comparison with the analytical method in order to achieve the required compensation accuracy. For several machine tool types, a comparison is given regarding the control method of the TCP spindle displacement without sensors and with temperature sensors. The limits of their rational use are presented.

In this article, we propose a method for improving accuracy in calibrating Leeb hardness testers using fiber interferometric systems. The calibration system is implemented using the photonic Doppler velocimetry technique. This paper provides estimates of the measurement uncertainty arising in the calibration system and describes a method for improving accuracy, which takes into account the signal-to-noise ratio, sampling rate, and processing parameters.

Static and dynamic stiffness [N/m] determine the ability of solids to resist constant and variable loads. Both elastic characteristics of a machine tool effect their quality assessment. Thermal stiffness (comprising heat stiffness and temperature stiffness) [W/µm] is a key accuracy indicator of the machine tool's ability to resist temperature influences. The proposed method creates the thermo-physical structure of a machine tool, based on a set of homogeneous heat-active elements and quasi-thermostable links. Quasi-thermostable links retain constant properties when the thermal state of the heat-active elements changes within a given range, building and determining their spatial and temporal relative position. The structural formula is given: < S-thermal link > - - . When exposed to heat, heat-active elements change their temperature and thermoelastic properties change their temperature and thermoelastic properties with stress, strain, distortion. Thermal behavior F-functions characterize these changes over time. Thermal energy causes a heat exchange in the machine tool and leads to temperature differences, thermoelastic stresses and geometrical deformations. The material used in machine tools enables the thermal conduction, convection and radiation due to its dimensions, volume and surface area, thermal conductivity. Elasticity effects base on thermal linear expansion coefficient, modulus of elasticity, thermal energy storage due to its heat capacity. The analysis of the structural formula defines and describes generalized thermal stiffness indicators of a machine tool as a reaction to thermal effects when the heat sources are constantly active and when the heat source is absent, but only the ambient temperature changes. This paper presents relationships between the thermal stiffness and the thermo-physical property indicators of the machine tool. Examples of thermal stiffness are described for several machine tool types.

Typical temperature and thermoelastic models of structures of spindle units and ball screw systems of metal-cutting machines were considered. The features of determining the geometric and thermophysical parameters of these models were described in some detail. Both analytical and numerical solutions for estimating time-dependent temperatures are presented. The solutions were obtained for thermoelastic displacements of spindles and ball screw systems for various boundary conditions and limitations of deformations during heating due to the design of these elements of metal-cutting machines.

The paper describes a method for measuring the surface area function of the tips of the probes of nanohardness testers using a laser interferometer. The features of the developed system provide traceability of measurements to the standard of length through the wavelength of a stabilized source of laser radiation. In addition, it is possible to measure the parameters of the probe tip without removing it from the nanohardness tester, which allows the device not to be taken out of working condition and provides unambiguous measurements.

On the basis of recent information regarding conduction, analysis of heat transfer by the response function method is proposed. Comparison with the finite-element method confirms the high accuracy of the proposed approach.

The report presents a laser diagnostic system designed to analyze the behavior of a matter in extreme states and the propagation of shock waves. The research system consists of a pair of velocity interferometer systems for any reflector (VISAR), push pull and conventional VISARs, forming a vernier scheme. This configuration was designed for Angara-5-1 facility. Test experiments of metal plate acceleration using magnetic field were carried out. The velocities up to 6 km/s were obtained.