Copper base alloy was overlaid onto 35CrMnSiA steel plate by tungsten inert gas (TIG) welding method. The heat transfer process was simulated, the microstructures of the copper base overlay were analyzed by scanning...Copper base alloy was overlaid onto 35CrMnSiA steel plate by tungsten inert gas (TIG) welding method. The heat transfer process was simulated, the microstructures of the copper base overlay were analyzed by scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS), and the friction and abrasion properties of the overlay were measured. The results show that the Fe content increases in the overlay with increasing the welding current. And with the increase of Fe content in the overlay, the friction coefficient increases and the wear mechanism changes from oxidation wear to abrasive wear and plough wear, which is related to the size and quantity of Fe grains in the overlay. While with the increase of Fe content in the overlay, the protection of oxidation layer against the oxidation wear on the melted metal decreases.展开更多
Hydrogen diffusion in the wall of hydrogenation reactor for three situations, i.e. operating, normal shutdown and abnormal shutdown, was numerically simulated based on the finite element program-ABAQUS. The formula of...Hydrogen diffusion in the wall of hydrogenation reactor for three situations, i.e. operating, normal shutdown and abnormal shutdown, was numerically simulated based on the finite element program-ABAQUS. The formula of diffusion-induced stress was deduced for model of the thin walled cylinder. Distribution of diffusion-induced stress in the wall of hydrogenation reactor was studied. The results showed that the maximum stress was at the fusion surface between welding overlay and base metal and which would increase with cooling rate. The crack will initiate and propagate from fusion surface to welding overlay when the diffusion-induced stress is higher than yield stress, but it will not propagate to the base metal. Diffusion-induced stress is one of the important factors for crack initiation and propagation of welding overlay of hydrogenation reactor.展开更多
Metallurgical equipment is subjected to severe working conditions and the components suffer from various types of physical damages such as abrasion,corrosion and crack. Advanced surface engineering technologies and re...Metallurgical equipment is subjected to severe working conditions and the components suffer from various types of physical damages such as abrasion,corrosion and crack. Advanced surface engineering technologies and resistant coatings on the damaged surface can improve surface properties, extend service lives, reduce maintenance costs and improve product quality in the metallurgical industry. This paper introduces remanufacturing technologies, including electroplating, overlaying welding, thermal spraying and laser surface cladding and their applications in the metallurgical industry, and analyzes the development tendency and prospect of remanufacturing technologies.展开更多
文摘Copper base alloy was overlaid onto 35CrMnSiA steel plate by tungsten inert gas (TIG) welding method. The heat transfer process was simulated, the microstructures of the copper base overlay were analyzed by scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS), and the friction and abrasion properties of the overlay were measured. The results show that the Fe content increases in the overlay with increasing the welding current. And with the increase of Fe content in the overlay, the friction coefficient increases and the wear mechanism changes from oxidation wear to abrasive wear and plough wear, which is related to the size and quantity of Fe grains in the overlay. While with the increase of Fe content in the overlay, the protection of oxidation layer against the oxidation wear on the melted metal decreases.
基金supported by Graduate Student Scientific Innovation Project of Jiangsu Province (No.CX09B 131Z)
文摘Hydrogen diffusion in the wall of hydrogenation reactor for three situations, i.e. operating, normal shutdown and abnormal shutdown, was numerically simulated based on the finite element program-ABAQUS. The formula of diffusion-induced stress was deduced for model of the thin walled cylinder. Distribution of diffusion-induced stress in the wall of hydrogenation reactor was studied. The results showed that the maximum stress was at the fusion surface between welding overlay and base metal and which would increase with cooling rate. The crack will initiate and propagate from fusion surface to welding overlay when the diffusion-induced stress is higher than yield stress, but it will not propagate to the base metal. Diffusion-induced stress is one of the important factors for crack initiation and propagation of welding overlay of hydrogenation reactor.
文摘Metallurgical equipment is subjected to severe working conditions and the components suffer from various types of physical damages such as abrasion,corrosion and crack. Advanced surface engineering technologies and resistant coatings on the damaged surface can improve surface properties, extend service lives, reduce maintenance costs and improve product quality in the metallurgical industry. This paper introduces remanufacturing technologies, including electroplating, overlaying welding, thermal spraying and laser surface cladding and their applications in the metallurgical industry, and analyzes the development tendency and prospect of remanufacturing technologies.