Technical Physics, Vol. 48, No. 8, 2003, pp. 1001–1008. Translated from Zhurnal TekhnicheskoÏ Fiziki, Vol. 73, No. 8, 2003, pp. 62–70. Original Russian Text Copyright © 2003 by Drennov, MikhaÏlov, Nizovtsev, RaevskiÏ. SOLIDS Perturbation Evolution at a Metal–Metal Interface Subjected to an Oblique Shock Wave: Supersonic Velocity of the Point of Contact O. B. Drennov, A. L. MikhaÏlov, P. N. Nizovtsev, and V. A. RaevskiÏ All-Russia Research Institute of Experimental Physics, Russian Federal Nuclear Center, Sarov, Nizhni Novgorod oblast, 607190 Russia e-mail:
[email protected] Received December 30, 2002 Abstract—The perturbation evolution at the interface between identical metals (metal plates) that is exposed to high-speed oblique shock waves is observed experimentally for the first time (the waves are attached to the point of contact, so that a cumulative jet cannot form). The experiments are numerically simulated by the two- dimensional Lagrange method. An elastoplastic model where the dynamic yield strength is a function of mate- rial state parameters is employed. An analytical technique to treat instability development under given loading conditions is suggested. High strains produce a high-temperature zone near the interface (thermal softening zone). A short-lived shear flow with a high velocity gradient depending on the angle and velocity of plate col- lision is observed. In this zone, the shear modulus and the yield strength are appreciably lower than under nor- mal conditions, which favors instability development. © 2003 MAIK “Nauka/Interperiodica”. INTRODUCTION forms in the collision zone. With vc > vcr, attached High dynamic pressure in metals may be produced oblique shock waves set up at the point of contact.