This paper presents the findings of fatigue strength tests of 15CrNi6 steel following low-pressure carburizing and oil quenching, subjected to cycles of one-sided three-point bending. The fatigue fractures were compared with the results of fatigue strength studies of 16MnCr5 steel following low-pressure carburizing and nitrogen quenching. The fatigue tests for 16MnCr5 steel were conducted as part of a high-cycle resonance test, with a pendular bending load. The study also involved an analysis of the effects on non-metallic inclusions in the structure on the mechanism of fatigue destruction. The inclusions were found to initiate fatigue cracks. In both cases, a similar method of a fatigue fissure initiation was observed, independent of the study method or specimen material.
The article presents the results of studies on the efficacy of water desalination (i.e. Elimination of NaCl ions from the solution) using graphene-polyamide composite membranes. The membrane used for filtration consists of a monolayer of polycrystalline graphene on a porous polyamide carrier support (nylon 66). The degree of desalination for an aqueous NaCl solution percolated through the membrane was 18%. In the future this type of membrane may replace the currently used reverse osmosis membranes.