Some Thermomagnetic and Mechanical Properties of Amorphous Fe75Zr4Ti3Cu1B17 Ribbons

The microstructure, revealed by X-ray diffraction and transmission Mössbauer spectroscopy, magnetization versus temperature, external magnetizing field induction and mechanical hardness of the as-quenched Fe75Zr4Ti3Cu1B17 amorphous alloy with two refractory metals (Zr, Ti) have been measured. The X-ray diffraction is consistent with the Mössbauer spectra and is characteristic of a single-phase amorphous ferromagnet. The Curie point of the alloy is about 455 K, and the peak value of the isothermal magnetic entropy change, derived from the magnetization versus external magnetizing field induction curves, equals 1.7 J·kg−1·K−1. The refrigerant capacity of this alloy exhibits the linear dependence on the maximum magnetizing induction (Bm) and reaches a value of 110 J·kg−1 at Bm = 2 T. The average value of the instrumental hardness (HVIT) is about 14.5 GPa and is superior to other crystalline Fe-based metallic materials measured under the same conditions. HVIT does not change drastically, and the only statistically acceptable changes are visibly proving the single-phase character of the material.

Influence of accelerator energy parameters and silicon carbide microparticle sizes on the changes in magnetic field induction during their acceleration

This article contains the microparticle accelerator scheme, the methods, and the results of practical study of magnetic field induction and electromagnetic radiation formed during explosion product ionization and energy accumulation during explosive charge detonation, as well as the influence of some process parameters on its change. The purpose of this work is to study the influence of accelerator energy parameters and silicon carbide microparticle sizes on the change in magnetic field induction during their acceleration. The influence of technological parameters on the electrodynamic properties of the ionization process of a complex chemical system, which is condensed EXPLOSIVES, was studied by the developed method based on the Hall effect with the use of the developed semiconductor Hall sensors and a special measuring complex. The average magnetic field induction value is 48 MT. The influence of the energy parameters of the accelerator (explosive charge mass), as well as of the size of microparticles introduced into the explosion products (PV) on the electrodynamic properties of the processes of ionization and acceleration of microparticles was determined by measuring and calculating magnetic field induction. Practical results were obtained and confirmed the particle size influence on the plasma state. With an increase in the particle size from 20 to 100 microns, the induction value increases to 50 MT and decreases sharply with a change in the size from 150 to 300 microns. The obtained dependences are the technological characteristics of the process of processing materials by high-speed flows of microparticles with the use of explosion energy, which can be adjusted to make the process manageable.

Mathematical Model of Tubular Linear Induction Motor

Problem of calculation of distribution of magnetic field induction in clearance of tubular linear induction motor (TLIM) is considered. Mathematical model is represented by Fredholm integral equations of second kind for complexes of electric field strength and density of coupled magnetization currents at interface of environments. Algorithm of calculation of distribution of magnetic field induction in TLIM clearance has been developed. Dependence of magnetic field induction in motor clearance on value of pole division is investigated. There is area of optimum pole pitch. Reliability of results of calculations on mathematical model is confirmed by their comparison with results obtained on physical model. Calculated dependence of induction on thickness of runner's iron circuit also has extreme character. Given model can be used at design stage of TLIM. Model allows calculating its optimal geometric dimensions based on criterion of maximum induction in motor clearance, taking into account physical properties of applied materials.

Measurement of the difference in the geomagnetic induction between the magnetometer pillars of the geomagnetic observatory of the Ukrainian Antarctic Akademik Vernadsky station

The article describes the features of measurements of spatial inhomogeneities of the geomagnetic field between the pillars of magnetometers in the measuring pavilion, which were carried out at the geomagnetic observatory of the Ukrainian Antarctic Akademik Vernadsky station in 2015. Some preliminary results of these measurements are also given. The concept of the timescaled value of the geomagnetic field induction is introduced, which is convenient for compensating for time changes of the real geomagnetic induction and bringing it to one reference level of induction. The differences in geomagnetic induction between pillars are obtained as the differences in time-scaled values of the geomagnetic induction on the pillars. The technique allows comparing long-term series of measurements of field inhomogeneities at important points in space. The main objectives are to increase the accuracy of measurements of local inhomogeneities of the geomagnetic field in the measuring pavilion of the geomagnetic observatory of the Ukrainian Antarctic Akademik Vernadsky station and to determine the differences in the geomagnetic induction between the pillars on which the magnetometer sensors are installed. Obtaining numerical values of the differences in the geomagnetic induction between the pillars as objective criteria needed to assess the accuracy of the data in the final processing of geomagnetic observatory data. The method of comparison of two series of data is used: one obtained by the scalar magnetometer installed in the observatory as a mandatory stationary device, and the other obtained during measurements with a mobile magnetometer at the desired points in space. Compensation of temporal changes of the geomagnetic field by time-scaling the measurement readings of the mobile magnetometer relative to one reference value and thus, bringing them to one selected and fixed time epoch. Special geometric scheme of mobile measurements in the space around the pillars with magnetometer sensors or at important points in space. A rough estimate of method errors. Based on the analysis of the obtained data, the efficiency of the method and its acceptable potential accuracy were confirmed. We obtained approximate numerical values of the differences in the geomagnetic field induction between the pillars on which the magnetometer sensors are installed. Further increase in the accuracy of determining these differences is possible using modern devices of high accuracy and GPS-synchronization of mobile measurements.