The Wear Resistance During Oscillating Friction of Steel Specimens with Strengthened Nanocrystalline Layers

Thermo-deformation treatment refers to methods of surface strengthening using highly concentrated energy sources. In the process of processing, the surface layers of the metal are modified, and strengthened white layers with a nanocrystalline structure are formed. The conducted studies showed that during the thermo-deformation treatment of the working surfaces of specimens made of steel 41Cr4 (quench-hardening and low-temperature tempering) using different technological media (mineral oil (MO), mineral oil with active additives containing polymers (APP) and saturated aqueous solution of mineral salts based on magnesium and calcium chlorides (ASMC)), a strengthened white layer with a thickness of 160 μm to 260 μm and a hardness of 7.6–8.2 GPa was formed. It is shown that the technological medium used during thermo-deformation treatment affects the wear resistance with reversible friction without lubrication. Thus, when using APP and ASMC, the wear resistance of steel-bronze friction pairs increased by 3.1–3.3 times, and when using MO, by 2.1–2.5 times, compared to the non-strengthened pair. During studies of friction pairs of “Steel 41Cr4 – Bronze CuAl10Ni5Fe4”, “Steel 41Cr4 – Steel 30HGSA” in oscillating (reversible) friction without lubrication, as well as single-direction sliding friction, strengthened white layers with a nanocrystalline structure significantly increase their wear resistance.