Our topic is irreversible or plastic deformation of structural elements
composed of relatively thin ductile materials. These deformations are
commonly used in sheet metal forming operations to produce lightweight
parts of any particular shape. In another context, this type of plastic
deformation is described as impact damage in the case of structural
components involved in collision. Here we are concerned with mechanics
of both static and dynamic deformation processes. The purpose is to use
typical material properties and structural characteristics to calculate
the deformation for certain types of load; in particular to find the
final deflection and shape of the deformed structure and to illustrate
how the development of this final shape depends on the constitutive
model used to represent the material behavior. The major issue to be
addressed is which structural and constitutive properties are important
for calculating response to either static or brief but intense dynamic
loads. Furthermore, how do the results of various constitutive models
compare with observed behavior.