Laws governing the discontinuous yield of metal on subjecting construction materials to tensile strain in liquid helium

Peculiarities of neck formation under low-temperature discontinuous yield of metals. Part 1. Axisymmetric deformation

“…Specimens were subjected to a static tension test according to the requirements of [5] on a UMN-10 machine [8] in liquid helium at 4.2 K. The rigidity of the loading system, which is not regulated by the standard [5], was 14.5 MN/m. As measurements show, the most marked necks with the smallest cross-sectional area are observed in specimens of 03Kh20N16AG6 steel, and the most raised neck, in which fracture occurs, corresponds to the last jump, which agrees with the results obtained in [9]. The intensification of deformation localization in the last jump is facilitated by the deformation damage of the material accumulated just in this neck as its influence is qualitatively analogous to temperature softening [10].…”