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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1561 Al. alloy U imp = 590 m/s ht = 6,56 mm himp = 2,0 mm

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Fig.4. Oscillations at the top of plastic front in 1561 aluminum alloy.

4. Microstructure investigations. In order to reveal the mechanism of shock-induced structural instability of studied materials, the microstructural investigations of post-shocked specimens has been performed. All the specimens were cut along the wave propagation direction and studied with “Obsevier - Z1”microscope. The structure of both kinds of aluminum alloy consists of heterogeneous elongated grains. Herewith, the structure of 1565 aluminum alloy has a much more texture features. In 1565 alloy the dimensions of grains range within 5-50 whereas in 1561 alloy within 5-120 µm. The concentration of intermetallides at the grain boundaries in 1565 alloy is much smaller as compared with 1561 alloy (see Figs. 5).

F ig.5. Microstructure of 1561 aluminum alloy (a) and 1565 alloy (b) .