Сравнение качества поверхностного слоя и эксплуатационных характеристик деталей, упрочненных разными способами поверхностного пластического деформирования

Abstract

The purpose of this work is comparison of the surface layer quality of samples treated by new hardening methods and by traditional rolling with a roller. The obtained results of the work are based on experimental studies where it was found out that the quality of the surface layer obtained by oscillating burnishing is higher than the one obtained by rolling but lower than the one obtained by transverse rolling with flat plates. Grain sizes change only in the surface layer, the central region practically is not subjected to plastic deformations and the grains do not change their sizes. The area of significant grain distortion extends to the depth of 0.1-0.2 mm with transverse rolling with flat plates and oscillating burnishing and to 0.1 mm under rolling with a roller. The microhardness and hardness obtained under oscillating burnishing is more than under rolling with a roller, but less than under transverse rolling with flat plates. The smallest deviation from roundness of cylindrical parts was obtained under transverse rolling with flat plates (2.9 times), and under rolling with a roller it is 2.1 times. The maximum axial residual stress is obtained under oscillating burnishing, then under rolling with a roller and transverse rolling with flat plates (1.8 times). However, the greatest tangential stress is formed under transverse rolling with flat plates, and the minimum stress under oscillating burnishing (1.3 times). Wear resistance of hardened samples is several times higher than the wear resistance of samples without hardening. The maximum wear resistance is characteristic of the parts reinforced by transverse rolling with flat plates, and the minimum wear resistance - of parts reinforced by rolling with a roller.