Analysis Of Interfacial Diffusion Between Nickel-based Self-fluxing Alloy Coating And Steel Substrate

Research and analysis on the diffusion phenomenon of interfacial region between two phases are of great importance to the practical application and the establishment of basic theoretical system of material science.This paper adopts the vacuum brazing furnace cladding process for the preparation of Ni-based self-fluxing alloy coatings under the temperature of1070?in heat preservation conditions.Mechanical combination between coating and substrate transforms into metallurgical bond by the migration of atoms on both sides.The"white band"is formed.The diffusion layer structure between the Ni-based self-fluxing alloy coating and the 316stainless steel,YT01 iron,Q235A steel,A45 steel and T10 steel substrate is stuied by using scanning electron microscopy.Different degrees of diffusion layer is formed between the Ni-based self-fluxing alloy coatings and 316 stainless steel,YT01 pure iron,Q235A steel,A45 steel and T10 steel substrate.The thickness and the change of form are analysed on the basis of the experimental results under the cladding temperature of 1070?in the heat preservation for 5 min,15min,25min,35min.The forming process of diffusion layer are analyzed and discussed on.The diffusion layer structure is analysed by using energy spectrometer and X ray diffraction.The interface migration between the Ni-based self-fluxing alloy and the steel substrate is mainly the migration of Ni atoms in coatings and the Fe atoms in steel substrate.The Ni atoms in the coating move to the substrate diffusion mainly,the main phase of diffusion layer is?-Ni-based solid solution,the new compound phase of FeNi₃ and CrB are found at the interface.In addition,the new compound phase Cr₃Ni₂Si is found on the Q235A steel specimen.The diffusion layer specimens are corroded using 10%HCL solution,corrosion resistance on the diffusion layer of 316 stainless steel specimens,YT01 pure iron specimens,Q235A steel specimens,A45 steel and T10 steel specimen is tested and compared with the corrosion resistance of the Nickel-based self-fluxing alloy.The amount of corrosion on diffusion layer in the acid solution is significantly less than Ni-based self-fluxing alloy.The reason of the good performance on diffusion layer is that the diffusion layer contains element Ni and Cr which have corrosion resistance,and a fine morphology appears on the Ni based solid solution in the bonding area which has good corrosion resistance after vacuum brazing.