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Experiments on the acceleration of a flyer by a magnetic field make it possible to study the dynamic characteristics of matter on submicrosecond time scales. Megabar pressures at the Angara-5-1 facility are produced using the magnetic field of the current with a linear density of up to 5 MA/cm. In the previous experiments on the acceleration of a duralumin flyer, velocities of up to 10 km/s were achieved. The flyer motion was recorded by means of laser shadowgraphy. In this work, the efficiency of momentum transfer from a duralumin flyer to an initially immobile tungsten target was studied. From the kinematic parameters of the flyer motion before the impact and the motion of the flyer together with the target after the impact, the fraction of the flyer mass that transfer the momentum to the target was estimated. It is established that almost the entire mass of the flyer is involved in the impact process. [ABSTRACT FROM AUTHOR]

Experiments on the creation of megabar pressures and acceleration of metal flyers by the pressure of a pulsed magnetic field are being carried out at the Angara-5-1 facility. Velocities of up to 10 km/s were achieved. The velocities of flyers were recorded using the VISAR laser interferometer (velocity interferometer system for any reflector). The issues of the electromagnetic compatibility of the VISAR with the Angara-5-1 facility are considered, since the operation of this facility causes electromagnetic interference and when the magnetic self-isolation is established in the vacuum transmission lines, X-ray bremsstrahlung is generated and influences the optics, fiber-optic cables, and photomultipliers. The suppression of these two sources of interference made it possible to reliably register the VISAR signals and determine the velocity of a flyer. [ABSTRACT FROM AUTHOR]

The acceleration of a flyer by a magnetic field allows studying the dynamic characteristics of matter in submicrosecond processes. At the Angara-5-1 facility, pressure is created by a magnetic field of the current with the linear current density of up to 5 MA/cm. The velocity of up to 10 km/s was obtained in the first experiments on acceleration of a duralumin flyer 1 mm thick. Two methods are used for registration of the flyer velocity: laser shadow photography and VISAR interferometric method. This paper presents the results of experiments on determining the velocity of a flyer by the VISAR method. Particular attention is paid to the problem of suppression of spurious signals in the VISAR registration system. The first problem was electromagnetic interference emerging when the Angara-5-1 facility is activated, when megavolt voltages and megaampere currents are generated within a hundred nanoseconds. The second problem was bremstrahlung radiation emerging when magnetic self-isolation is established in vacuum transmission lines. This radiation affects the optics, fiber optic cables, and photomultipliers. The suppression of these two sources of interference ensured the reliable registration of the VISAR signals. The results obtained by the two laser methods—shadow photography and VISAR—coincide with each other and with the results of numerical simulation of flyer acceleration. The experimental results and simulation results are compared. [ABSTRACT FROM AUTHOR]

The output unit of the Angara-5-1 installation was upgraded in order to increase megabar pressure. Upgrading was carried out taking into account those fact that pressure was created using the magnetic field of the current flowing through the specimen. To increasing the power impulse acting on the flyer from the side of the magnetic field, variants of increasing the time duration of the magnetic field were considered by controlled current shorting (crowbar). In accordance with the mathematical simulation when extending the current pulse, it is possible to increase the flyer velocity by a factor of two. [ABSTRACT FROM AUTHOR]