Investigations of Wear Resistance of Hardfaced Layers on Steel 40X

Abstract

The article discusses a fundamental problem in the shipbuilding industry related to the repair of critical and expensive components directly related to the operation of ships in the global fleet. Methodology and technology for repair by welding of workpieces made of 40X steel have been developed and applied. Hardfacing electrodes of the brands OK 83.28 and OK 61.20 were used. The developed welding technologies include both buffered and non-buffered layers. For one of the specimens, preheating to a temperature of 200 degrees Celsius was performed, which proved to be optimal for the metal. The measured macro stresses are below the elastic limit of the examined metal. The measured residual stresses are insignificant at +62 MPa. The microhardness results show an increase in microhardness to about 450HV in the weld metal zone. The dry friction wear test performed on the welded layer showed a relatively uniform metal loss in both specimens due to the slight increase in temperature.