Resistance of submicrocrystalline aluminum alloys to high-rate deformation and fracture after dynamic channel angular pressing

A comparative study of the deformation behavior of submicrocrystalline (formed by dynamic channel angular pressing) and coarse-grained commercial aluminum alloys (AMts and V95), and commercial aluminum A7 has been performed under impact compression conditions. Dynamic elastic limit (Hugoniot elastic limit) σ HEL , yield strength Y , and spall strength σ sp at a deformation rate of (1.2–3) × 10 5 s −1 were determined by analyzing the experimental velocity profiles of the free surface of samples. It has been found that the dynamic elastic limit and yield strength increase after all the materials studied have transformed into a submicrocrystalline state (crystallite size of 200–700 nm). Submicrocrystalline alloy V95 has the highest value of Y and submicrocrystalline aluminum A7 has the lowest one. The effect of grain size on spall strength is ambiguous. The values of σ sp for submicrocrystalline alloys are 1.32–1.36 GPa. The submicrocrystalline V95 alloy and commercial A7 aluminum demonstrate a decrease in the spall strength, whereas the spall strength of the alloy AMts slightly increases with decreasing grain size.