Void evolution of micro/nanocrystalline Ni under uniaxial compression

To study the effect of pores on the mechanical properties of porous bulk micro/nanocrystalline Ni sample further, a model of pore evolution under uniaxial compression test was firstly established on the basis of the emission of geometrically necessary dislocations due to the mismatch between the pore and matrix. At the same time, a new constitutive relation considering the evolution of porosity under uniaxial compression was proposed, and the evolution of the porosity was described quantitatively. Then, the effects of constant porosity and evolution porosity on the mechanical behaviors of micro/nanocrystalline Ni with different grain sizes and strain rates were disscussed.