Abstract
A thermodynamic model is derived to study the void nucleation in ideal lattices under hydrostatic tension loading and predicts that the plasticity has to be initiated before homogeneous nucleation of voids. Molecular dynamics simulations are performed to evaluate the mechanical behavior of Ni specimens with and without hydrogen charged. The results show that in both cases dislocations are generated before the nucleation of voids, and the insertion of hydrogen atoms does not alter the void nucleation significantly. The fact that the mechanical property is not sensitive on hydrogen is attributed to the formation of an amorphous shell around the voids.