The Study Of Pre-coating And Its Cladding By Electrical Contact Heating On Astm1045 Surface

In the process of production,the parts keep moving and friction,to achieve the transfer of energy,the transfer of motion.In this process,the surface of the workpiece is subjected to a large load,which leads to various abrasion and failure.At this time,various coating reinforcement techniques can be used to improve the abrasion resistance of the parts surface.There are many ways to prepare the coating on the surface of the parts,but the coating and the substrate are usually mechanical,and the surface coating of the substrate is strengthened by electric contact,which can realize the metallurgical combination of the substrate and the coating.Therefore,it is necessary to study the technology of electric contact strengthening of the coating.In this project,the author is based on the technology of adhesion and electric exposure,and selecting 45 # steel as the base,the Ni60-WC powder as the material of the pre-coating,the acrylic glue and the epoxy glue as the glue.Then using the adhesive technique to coat the surface of the 45 # steel body with a coating of pre-coating,and then using the power of the self-developed technology of DongHua University to acquire the high-performance coating.the method is effective to improve the coating's organization and mechanics,reduce the energy consumption,reduce the cost.The obtained coating has excellent binding performance and strong abrasion resistance.This topic is based on the workpiece surface strengthening experiment research,the emphasis is on the process of selection of binder,each technical parameter setting and the improvement of the performance of the coating after secondary reinforcement.The main study is the ratio of the binder,the ratio of the alloy powder to the binder,and the electrical current in the electrical contact,the pretension of the electrode wheel,and the time of the electrical contact and the critical parameters of the pre-coating to enhance the performance of the pre-coating in the process of adhesion and electrical contact.In the end,the samples were made into metallographic samples,The metallographic structure was analyzed by using the ultrasonic microscope,scanning electron microscope was used to observe the finished coating and test coating particles distribution and diffusion,the coating hardness and bonding strength.The research shows that the combination of adhesive coating and electric contact strengthening technology can make the surface of the matrix have no obvious defects,and the density of the structure can be enhanced,and the hardness and bonding performance of the coating can be improved obviously after the secondary reinforcement.Through multiple experiments,it is concluded that the optimum ratio of the alloy powder with the binder is 1:1.5,and a series of electrical and electrical parameters are determented.The enhanced coatings were analyzed,microhardness tested,substrate surface scanning at the boundary of the coating.Through the analysis,it is concluded that after the electrocontact enhancement,the coating is less flat,less defective,more rigid and resistant to the abrasion;The thickness of the coating is further increased after the secondary electrical contact strengthening,and the tissue is more dense,which can repair the defects left by the reinforcement in a certain degree,and the substrate performance of the improved electric contact is improved obviously.