Effect of the microstructural porosity parameters on the fracture and deformation of copper during creep at 773 K

The parameters of intergranular fracture of copper during creep under tension at $T$ = 773 K and $\sigma$ = 12.5 MPa are determined, and the contribution of grain-boundary porosity to the increase in the creep rate at stage III is estimated. The increase in the creep rate is shown to occur due to the pore-induced decrease in the grain boundary area, an increase in the mobile-dislocation density, and the deformation of the material because of the formation of pores and cracks.