Phase and Structural Transformations of Structural Steels in Nontraditional Heat Treatment

摘要

In heating structural steels to extreme temperatures with quenching or normalization, the dislocation density in the α-phase structure is comparable with that on heating to the standard temperature Ac_3 + 30-50°C. The change in dislocation density depends on the quantity of carbon and alloying elements in the steel. In manufacturing and in repair shops, it is important to decrease the consumption of metal and energy. Since most components are produced from carbon and low-alloy steels, whose life is mainly determined by their mechanical properties, they are strengthened by heat treatment: quenching with tempering. The standard heat treatment for metal components ensures good mechanical properties, as a rule, but deficiencies are evident in some cases. In particular, the ductility may not be sufficient to ensure the required reliability [ 1 ].