Dynamic spherical indentation of strain hardening materials with and without strain rate dependent deformation behavior

Dynamic spherical indentation of elastic-plastic solids is examined in the light of finite element simulations. The deformation behavior of indented solids is described by two constitutive models - elastic-plastic strain hardening with or without strain rate dependent deformation. Numerical results of dimensionless global field parameters that describe the deformation response, such as mean contact pressure, contact area, and plastic work, are presented for a range of indentation velocity and elastic-plastic material properties. The dynamic contact response is interpreted in terms of a dimensionless indentation parameter, the normalized indentation strain, and the strain hardening and strain rate dependent material properties. It is shown that generalized solutions of global field parameters can be obtained in terms of the indentation parameter and indentation strain over a certain range of indentation depth. The results of this study provide new insight into the role of strain hardening and strain rate dependent deformation on the dynamic contact response of elastic-plastic solids.