On fig. 5 structures of aluminum samples after static tests are presented. Porosity in a sample 4, cracks in a sample 5 and the main crack in a sample 6 is visible. a b c d Fig. 5. Structure of aluminum samples after static tests: a – in an initial condition; b – pores in a sample 4; c – crack in a sample 5; d – the main crack in a sample 6. In figure 6 structures of samples of copper after static tests are presented. a b c d Fig. 6. Structure of copper samples after static tests: a – in an initial condition; b – sliding strips in a sample 4; c– homogeneous structure in a sample 5; d – sliding strips in a sample 6. In samples 4 and 6 sliding strips are observed, and in a sample 5 the homogeneous structure prevails, as is noticeable by appearance of samples in fig. 4. The sample 5 is destroyed at an angle about 450, i.e. in the direction of the maximum tangent stress on the planes of more dense packing. 3. Deformation and destruction of aluminum and copper samples at dynamic loading Experiments on deformation and destruction of samples were carried out with use of the modified magnetic-pulse method on the basis of the generator of short high-voltage impulses of GKVI-300 providing formation of electric voltage with amplitudes of 30 - 300 kV. As samples rings from thin aluminum and copper foils with a diameter of 28,6 mm and 1 - 2 mm wide were used. On fig.7 the loading scheme is shown. The current passing on the coil on which the ring sample coaxially settles down, directs in it induction current, and interaction of these currents generates pushing away force between the solenoid and a ring.The coil is made of a copper wire by diameter 1mm, has 5 rounds, diameter of the coil - 25 mm. The current passing through the coil, was measured by a Rogovsky coil (RC) and displayed on a digital oscillograph (OSC) information with which registered on the electronic carrier. At a rupture of the ring (Sample) which has been coaxially fixed on the middle of the coil (L), there was a spark which allowed to fix the moment of destruction of a sample by means of the photo diode (PD). At test of samples installation when via the coil current with the period of fading fluctuations Т=1µs was passed was applied. Its flowchart is provided on fig. 8. Appearance of installation is given on fig. 9. On fig. 10 current oscillograms via the coil and a signal from the photo diode fixing the moment of a rupture of a sample are represented. Experiments on rings from aluminum and copper foils 0.015 mm thick and 1.0 - 2.0 mm wide were made. Samples tested with a cut and without a cut.
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