This work compares the mechanical behavior of alloys with influence of grain size distribution on the in a wide range of strain rates. Constitutive model was proposed for describing the inelastic deformation and damage of alloys with face centered cubic and hexagonal close packed structures and distribution of grain sizes. It was shown that the dependences of the yield stress on logarithm of normalized strain rate for aluminium and magnesium alloys with a bimodal distribution of grains and coarse-grained alloys are similar. The yield stress at room temperature of the magnesium and aluminium alloy increased on 10 - 15 % in comparison with a coarse-grained alloy if the volume fracture of the UFG grains is close to the percolation threshold.
Funding Agencies|Grant from the President of Russian Federation [MK-2690.2017.8, C.-1916.2015.2]