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This paper investigates the changes in the properties of a bulk amorphous metallic alloy based on the ferrum (Fe55Ni8Co6)69-(Mo4Cr2V1)7-Al2-(P9C6B5Si2)22 under the influence of an alternating magnetic field (AMF). The level of the structural ordering of the bulk samples is higher than that of their tape counterparts. A slower cooling rate causes a partial nanocrystallization. The surface of such bulk samples is covered by surface layers, which were formed during the synthesis. These layers determine the corrosion resistance of amorphous alloys in the investigated solutions. After holding the samples in the AMF, some alteration of their elemental composition can be observed. An analysis of the electrochemical characteristics of the alloy samples under the conditions of cyclic scanning of the electrode potential indicates a higher corrosion resistance of the tested samples in a solution of hydrochloric acid. The lowest corrosion resistance was in the aqueous NaOH solution. During multiple cyclic polarization of bulk samples in aggressive media, a passivation of the surface occurs, and the destruction of the surface protective layers. The samples of the alloy (Fe55Ni8Co6)69-(Mo4Cr2V1)7-Al2-(P9C6B5Si2)22 modified by an alternating magnetic field have increased corrosion resistance in a 0.5 M aqueous solution of NaCl and HCl. By choosing the duration of the modification in the alternating magnetic field, it is possible to change the electrochemical parameters of the alloy (Fe55Ni8Co6)69-(Mo4Cr2V1)7-Al2-(P9C6B5Si2)22. An alternating magnetic field contributes to the diffusion of atoms in the bulk, which will determine not only the electrochemical parameters of amorphous alloys, but also other physical and chemical properties of a multicomponent sample. Under the influence of AMF, the electrical resistance of the amorphous samples is significantly reduced with increasing exposure to the magnetic field [ABSTRACT FROM AUTHOR]

An influence of the elemental composition of the amorphous alloy, the shape of its final product, as well as the preparation conditions (cooling rate) according standard technology, on the strength characteristics of tape and bulk samples of alloys made from the same feedstock is investigated. A lower cooling rate in the process of obtaining bulk alloys (10³ K/s) increases structuring of bulk samples, in comparison with tape samples (106 K/s), and causes higher divergence of surface elemental composition from the original feed-stock. Microhardness of the bulk samples is higher than one of tape alloys. [ABSTRACT FROM AUTHOR]

For the rational design and operation of the upgraded equipment, it is necessary to investigate the operation of the mechanism for regulating the shape of the belt cross-section, to determine its geometrical parameters at which productivity will be maximum. In order to increase work efficiency and expand the functionality of belt conveyors during the transportation of both bulk and piece goods the conveyor, containing a device for quickly adjusting the shape of the cross section of the tape is designed. The middle roller with supports is fixed on the rigid frame of the conveyor and pivotally connected to external rollers, which in turn are fixed to the free ends on the ropes. The flexible rope suspension is mounted on lever devices, allow them to move branches in the cross section of the conveyor. This design allows to expand the possibilities of transporting various types of goods by creating for them the best operating conditions. A kinematic synthesis of the mechanism has been carried out, the forces that arise in kinematic pairs have been determined, and recommendations have been formulated for designing a mechanism for regulating the shape of a conveyor belt. It was established that the dimensions of the links decrease with increasing stroke of the leading link; the dimensions of the links decrease with increasing both the angle of inclination of the rocker arm in the lower position and its span; parameters of the compact tape changing mechanism are defined. For each structural group of the mechanism, force analysis has been carried out; its purpose is to determine the geometrical dimensions of the mechanism, at which the effort with which it will be necessary to move the control element will be the smallest. In order to design a mechanism for regulating the shape of a conveyor belt with the smallest overall dimensions and lesser driving force, it is necessary to bring the maximum possible values to the angle of the rocker arm amplitude and angle of rocker arm inclination in the lower position. It has been determined that the smallest force that must be applied to the device for quickly adjusting the cross-sectional shape of the belt will have a mechanism with a maximum swing arm angle of 42° and a greatest angle of inclination of the rocker arm in the lower position 30°. [ABSTRACT FROM AUTHOR]