Features of Dynamic Strain Aging of Low-Carbon Steels during Severe Plastic Deformation Processing

The paper considers the features of the manifestation of dynamic strain aging (DSA) effect during severe plastic deformation processing via equal-channel angular pressing of low-carbon steel 10 and during the deformation processing via rolling of steel 20Kh. The deformation mechanisms under different regimes of deformation processing are analyzed. The temperature ranges for the manifestation of the DSA effect during the deformation by rolling of steel 20Kh and by equal-channel angular pressing of steel 10 are established. It is demonstrated that the deformation of low-carbon steels in the temperature range of DSA leads to further structure refinement and, as a consequence, to the enhancement in strength properties.

Solution to the Diffusion Problem in the Thermocyclic Nitrocementation of Steel

It is shown that cyclic heating and cooling considerably accelerate kinetics of process of the steel chemical thermal processing. Laws of formation of the strengthened layers are considered at thermocyclic nitrocementation of the steel 20Kh. Production tests of machine parts after the chemical thermal and chemical-thermocyclic processing were performed. The structure, phase composition and intensity of wear process of a blanket depending on a number of cycles are studied.