THE PENETRATION PROCESS OF LONG RODS AT INTERFACES BETWEEN MATERIALS

摘要

Experimental and computational study was conducted to study the penetration mechanism of a long rod along the interfaces between different materials having significant different resistance to penetration. The purpose was to investigate the trajectories and penetration depths of the rods. A series of experiments was carried out employing long rods made of tungsten alloy, with aspect ratio of 17, shot at 1,400 m/sec. Multi-channel 150 kV and 450 kV flash x-ray systems were employed. The radiographs were used to monitor the interaaction between the rods and the targets Each tested target was made of two thick plates made of different materials with large lateral dimensions, attached to each other. The penetrators were shot at the interfaces between the plates. In one test the rod was shot along the lateral free surface of the plate. For the computational simulations the AUTODYN 3D hydrocode with the 3D LaGrange technique was employed. Material modeling for both rod and target was done with the Johnson-Cook model. Good agreement was found between the experimental observation and the calculated results. The simulation gave better insight into the different modes of the penetration mechanisms.