Surface Melting, Spallation, and Stresses Induced in Metals by Pulsed Electron Beam Heating

Abstract

The present study was undertaken to investigate the applicability of one-dimensional computer programs for predicting the response of materials exposed to rapid surface heating produced by a pulsed electron beam. A specific objective was to determine modifications necessary to account for surface melting and spall. Measured values of mass loss, impulse, and internal stresses in lead and gold were satisfactorily predicted using a one-dimensional finite-difference program which simultaneously solved the conservation equations and a hydrodynamic equation of state. Required program modifications included: (a) specifying spall to occur to the depth below the target surface at which the energy deposited was sufficient to initiate melting, and (b) revising the equation of state for the material in the two-phase region.