Microstructure and Properties of High Chromium Cast Iron Surfacing Layer on Surface of Tamping Tine for Railway

Different high chromium cast iron surfacing electrodes were used for surfacing repair of the failed tamping tine.Microstructure observation,hardness test and impact wear test were carried out to investigate the microstructure and properties of the surfacing layers,and the results were compared with those of a new tamping tine.The results show that the main microstructure was primary carbide(Cr,Fe)7C3 and eutectic structure.The carbides were hexagon or strip,whose content decreased from the surface to the bottom.The surfacing layer had better hardness and wear resistance than the new tamping tine,while the properties of the layer with JD2 electrode were better than those of the layer with JD1 electrode.