Investigation of structure, rheological and relaxation properties, and stress relaxation kinetics in nanocrystalline beryllium at hot rolling temperatures

Abstract

Rheological and relaxation properties of high-purity nanocrystalline beryllium are obtained at hot rolling temperatures. It is shown that full stress relaxation in nanocrystalline beryllium occurs only upon deformation. A pause between deformations caused by repeated compressions does not affect the stress-strain curve or the final grain size. It is established that initially nanocrystalline beryllium (with grain sizes of 30–40 nm) converts into fine-crystalline one (with grain sizes of 5–6 μm) after hot plastic deformation at T = 700–800°C. The results are necessary for the creation of nondestructive technology to produce the thinnest foil from nanocrystalline beryllium.