Deformation of lead disks under impact

The effect of relatively low-velocity (1–3 m/sec) impact on a thin disk of imcompressible viscoplastic material placed in the gap between parallel rough surfaces is considered. The state of stress of the interlayer is assumed nearly hydrostatic during impact, the duration of which is limited by the elastic deformation of the elements of the striker system. The mathematical problem of determining the distributions of stresses, velocities, and temperatures for the axisymmetric deformation of a disk is reduced to the integration of an ordinary second-order differential equation. Numerical calculations for certain cases of impact are compared with the results of experiments on lead samples. Plane strain of an interlayer of viscoplastic material between rigid plates moving with a constant velocity is discussed in [1]. The state of stress of the interlayer for the same conditions of motion of the plates was studied in [2] for axial symmetry. In the present paper we take account of the impact nature of the loading and the elastic compression of the elements of the striker system, factors on which the deformation and the pressure developed in the impact depend.