Abstract:Using pulse cold welding repair technology,the Q345 modified layer was prepared by remanufacturing the 45 steel substrate.The effect of energy output amplitude on the quality of repairing layer was studied.Metallographic microscope,scanning electron microscopy (SEM),energy dispersive spectrometer (EDS),Xray diffraction and microhardness were used to study the phase structure,microstructure,element diffusion and hardness distribution of the binding region between the substrate and the repairing layer.The results show the heat affected zone of the interface is very smaller after repairing.There is an obvious fusion area at the interface between the matrix and the repairing layer,and the element diffusionbehavior occurs at the interface.There are new phases such as γ(Ni,Cr,Fe),Co3Fe7and C0.055Fe1.945to be formed at the interface,showing it is metallurgical bonding between the matrix and the repair layer.The hardness of the repairing layer is lower than that of the matrix,which is convenient for subsequent machining.The quality of repairing layer with energy output amplitude of 40% is better than that with energy output amplitude of 90%,because the fusion zone on the substrate side occurs holes and tiny cracks when the energy output amplitude is 90%.
