Аннотация
Different variants of the hardness of the wheel/rail friction pair were investigated to determine the optimal hardness range of the wheel/rail that ensures the minimum wear under selected test conditions.A pair of tests was performed on an MI-2 machine with a cylindrical wheel steel roller and a rail steel liner.The hardness of the wheel steel specimens ranged from 275 to 900 HVw.The selected of the rail steel samples of 345-455 HVr covers the possible hardness variations (350-405 HVr) of R65 type long rails produced on the standard ST RK 2432-2013 "Railway Rails Differentially Hardened and Nonheat-strengthened." Technical Requirements.The optimal ratio of wheel/rail hardness, which ensures minimum wear due to weight loss of the tested samples, is the interval HVw/HVr-1.41-1.59.This ratio of wheel/rail hardness is practically confirmed when linear wear is determined by micrometric measurement of the impression size with HVw/HVr-1.39-1.56.The results of the laboratory tests and the suggestions for the optimal ratio of wheel/rail hardness to improve wear resistance should be verified under field conditions.Oscillography of the destruction process of plasma-hardened and nonstrengthened specimens was performed to evaluate the resistance to crack initiation and propagation.