Strain rate effects on the mechanical behavior of thick-walled pressurized cylinders

Resumo

This work studies strain rate effects on the mechanical behavior of thick-walled cylinders subjected to
internal pressure. The material is assumed to present an elastic-viscoplastic behavior presenting strain hardening,
strain rate hardening and instantaneous rate sensitivity. In an effort to elucidate the expected strain rate effects, the
thick-walled cylinder is assumed to radially expand due to an imposed displacement on its internal surface. The
influence of the imposed expansion velocity on the mechanical field that develops through the thickness is assessed
by means of an analytical solution and using finite element simulations. The analysis considers constant velocity
expansions and tests in which the expansion velocity is abruptly changed: stopped, decreased or increased. Such
imposed loading conditions allow evidencing instantaneous and strain rate history effects on the stress response
and on the material hardening behavior.