Basic Research Of Auto Parts Size Recovery Technology

With the rapid economic development,China’s auto production and auto possession are both in growth,resulting in a large number of scrap parts,which will inevitably lead auto parts remanufacturing to a new industry. The significance of auto parts size recovery research is to use the scrap parts with high added value,reduce the materials used in the production of new parts and save resources. To a certain extent,it will eventually solve the problems of global resources waste, environmental pollution and ecological imbalance.Structural steel is the common material used in auto parts,and45steel is also a commonly used carbon structural steel.This paper will simulate a variety of failure forms of auto parts on45steel specimens,such as even wear, flake, crack, scratch and so on.According to the difference on failure forms and performance requirements, adopting different size recovery technology to recover the size, and studying the composition,structure and related performance of recovered specimens. The main contents and conclusions are as follows:Ⅰ. With cold welding technology and stainless steel fill materials to repair the cracks and pitting spalling pits on the surface of45steel.After repair,the cold welding layer’s surface morphology shows that the weld-repair area’s fusion zone and heat affected area are very small, and the matrix grain near the fusion line has little changes. The matrix and fill materials belong to metallurgical bond after repair,and the binding strength is good.The surface of repair layer’s hardness is more uniform, there are no hard spots and local hardening. The main wear of cold welding layer is abrasive wear, adhesive wear is complementary. Under the same wear conditions, the friction coefficient of the cold welding layer is lower than the friction coefficient of the matrix.Ⅱ. Brush plating through a single brush plating fast nickel on the surface of45steel to determine the process parameters. On the basis of single brush plating fast nickel to study the sedimentary principles of composite brush plating.To make nickel as base metal of coating,trying to join the micron particles MoS2and nanoparticles SiO2as reinforcement,making MoS2/Ni coating and SiO2/Nicomposite coating respectively in order to in order to improve the performance of Ni-based coating. Doing an analysis on the surface morphology and EDS of single fast nickel coating, micron particles MoS2composite coating and nanoparticles SiO2composite coating to make sure that the two particles can join and adjust the composite brush plating’s process parameters.Ⅲ. To test and compare the hardness,bond strength,wear resistance and other relevant performance of the three coatings. MoS2/fast nickel coating’s hardness slightly higher than fast nickel plating’s,and SiO2/fast nickel compound nano brush plating coating’s hardness is the highest,obviously higher than the previous two coatings.The main wear of the three coatings is abrasive wear, adhesive wear is complementary. Adding anti-wear particles MoS2in plating solution will decrease friction coefficient of the coatings. And meanwhile adding wearproof particles SiO2in plating solution will increase the wear resistance.Through the study of cold welding method and composite brush plating technology,With cold welding method to repair45steel cracks and pitting pits,making micron particles MoS2and nanoparticles SiO2as reinforcement to compositely plate the large wear area of the45steel surface,which will provide theory basis and practical guidance for the repair of45steel auto parts.