Peculiar features of ultrafine-grained beryllium deformation within the range of 77 to 830 K

Temperature dependences of strength and plastic characteristics of fine-grained beryllium (up to 1.5 mcm) with technical purity (∼ 99,0 mas. %) prepared by means of mechanical-termal treatment of a casting are investigated. Plastic deformation peculiarities of this material are determined. It is shown, that peculiarities of mechanical properties are as follows: 1) weak temperature dependence of strength properties at temperatures lower, than 2.73-300 K; 2) abrupt decrease of σB within 2.73-300 K temperature range; 3) rather low value of brittle-ductile transition temperature (410 K)