Deep Penetration of Thick Thermoviscoplastic Targets by Long Rigid Rods

摘要

We analyze axisymmetric thermomechanical deformations of a thickthermoviscoplastic target being penetrated by a fast-moving rigid cylindrical hemispherical-nosed penetrator. The target material is assumed to exhibit strain and strain-rate hardening and thermal softening. The target penetrator interface is assumed to be smooth. In the solution of the problem by the finite element method, the mesh is refined automatically whenever one of its elements has been severely distorted such that a very fine mesh is generated in the region adjoining the target penetrator interface and the mesh size increases gradually as one moves away from this interface. The computed depth of penetration has been found to correlate well with the test values. We also give details of the deformation fields, such as the history of the temperature at a material point, contours of the pressure field and the distribution of the velocity field in the deforming region. (MM).