Jumplike Deformation as the Scale Effect Measure for the Metal Deformed Volume Under Deep-Freezing Conditions: Experiment and Modeling

Abstract

Tensile tests of titanium alloy and austenitic steel specimens have been conducted in the range of temperatures 300–4 K. Under deep-freezing conditions, there occurs a new type of scale effect – variation of low-temperature jumplike deformation, which causes a sharp variation of the plasticity characteristic (the relative elongation). The difference between jumplike deformation values in the maximum and minimum cross-sectional areas of standard cylindrical specimens is introduced as the scale effect measure. Via mathematical modeling performed for 03Kh20N16AG6 steel, we have obtained dependencies of the scale effect on the most critical factors – the trigger stress of deformation jump and specimen–test machine system stiffness. The scale effect nature is studied, and options of its minimization, in reference to the standardization of mechanical tests, are discussed.