PSI - Issue 6

Yurii Meshcheryakov et al. / Procedia Structural Integrity 6 (2017) 146–153 Author name / Structural Integrity Procedia 00 (2017) 000 – 000

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Fig. 2. Structural instability threshold for 1561 aluminum alloy ( 1 ) and for 1565 aluminum alloy ( 2 ).

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Fig.3. Oscillations at the top of plastic front in 1565 aluminum alloy (indicated by symbol *)

In our experiment, the temporal and space resolution of equipment allows the high-frequency oscillations of plastic flow to register for both kinds of aluminum alloy. In Fig.3 and Fig.4 the oscillations at the top of plastic front are shown for the 1565 and 1561 aluminum alloy targets. The period of oscillations which reflects a difference in response of aluminum alloys on impact, turns out to be distinguished by eight times: T = 7 ns for 1565 alloy and T = 47 ns for 1561 alloy. The mean sp ace period of oscillations equals 39 µm for 1565 aluminum alloy and 250 µm for 1561 alloy, respectively. Thus, the transition to heterogenization correlates with the period of oscillations at the plastic front – the smaller period of oscillations, the higher threshold of structural transition.