High-temperature drop in the plasticity of low-alloy steels

1. At temperatures below 1000°C, a sharp reduction in plasticity properties (plasticity drop) is observed in steels 16GFR, 17G1S, and 09G2FB. 2. A sharp (by hundreds of degrees) expansion of the temperature interval of the plasticity drop occurs as a result of cooling the specimens down to 800°C prior to testing; the magnitude of the effect depends on the characteristic features of the chemical composition of the low-alloy steels (microalloying, impurity content). 3. The question concerning the causes for the appearance of the plasticity drop must be considered in connection with the formation of segregations of harmful impurities on the grain boudaries in the austenitic temperature region.