PSI - Issue 6

V.A. Morozov et al. / Procedia Structural Integrity 6 (2017) 154–160 Morozov et al. / Structural Integrity Procedia 00 (2017) 000–000

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2. Materials and experimental techniques

The experiments were carried out on a generator of short high-voltage pulses providing formation of electrical voltages with amplitudes of (10 − 300) kV . Two electric loading schemes were used: low-voltage (10 − 24) kV one and high-voltage (100 − 300) kV one. These schemes allowed to realize strain rates of (10 4 − 10 5 ) s − 1 . A copper wire with a diameter of 75 µ m and length of 40 mm was used as an explodable conductor. It was was inserted into an axial hole with a diameter of (1 − 2) mm made in a cylindrical sample (see Fig. 1 and Fig. 2). Samples were made from PMMA and fluoroplast. Diameter of the samples made with fluoroplast was varied within the limits of (33 − 68) mm for a low-voltage loading scheme, and within (8 − 20) mm for the high-voltage one. The diameter of samples made with PMMA also varied in the range of (30 − 103) mm for the low-voltage loading scheme and within (30 − 50) mm for the high-voltage one. The length of the cylindrical samples was determined by the length of the exploding conductor and was ∼ 30 mm .

Fig. 1. Low-voltage loading scheme: 1 - autotransformer, 2 - rectifier, 3 charge resistance, 4 - capacitor, 5 - discharger, 6 - Rogovsky coil, 7 - exploded conductor, 8 - sample, 9 - oscilloscope, 10 - piezoelectric sensor.

Fig. 2. High-voltage loading scheme: R ch – charge resistance, C – capacitor, S – spark gap, IT – pulse transformer, FL – forming line, ED – output device, HVW – high voltage electrode, EW – exploded conductor, S ample – sample, P – piezoelectric sensor, RC – Rogowski coil, OSC – oscilloscope.