The Development And Analysis Of Shot Peening Process To Improve The Aluminum Conductor Steel Reinforced Corrosion Resistance

It is very important to explore the mechanism of the corrosion process and corrosion mechanism of the aluminum conductor steel reinforced (ACSR) and to find out a feasible anti-corrosion method to delay its atmospheric corrosion, which will improve the service life and reduce the cost of electric power transmission. The task aims to improve the defects on the surface of the ACSR using shot peening technology, and combined with low temperature heating oxidation to eliminate the residual stress, at the same time promote the reconstruction of the oxide film, in order to improve ACSR’s resistance to atmospheric corrosion.Deal the ACSR and single aluminum wire sample respectively with four kinds of processing, non processing, pre-oxidation, shot peening, shot peening+pre-oxidation, perform neutral salt spray test and copper acetate accelerated salt fog test referring to GB/T10125-1997. Obtain the kinetics curve of weight average, sample analysis including before and after test analysis. Use SEM and XRD to check the morphology of the sample appearance structure and surface microscopic stress. Adopt the method of electrochemical measurement to test the corrosion resistance. After test, analyze the surface and cross section corrosion morphology of single Al wire and ACSR, and analyze the corrosion products, test the polarization curve.From the data analysis we obtained the dynamics of the corrosion rate and surface stress, the relationship between the state of surface oxide film; and obtained the relationship between electrochemical properties with surface stress and the state of surface oxide film. Results show that the shot peening and pre-oxidation process were able to increase the ACSR’s corrosion resistance, and shot peening+pre-oxidation process is a much more effective process to improve the corrosion resistance.Our analysis suggested that pre oxidation process released the grain distortion of aluminum conductor, reduced defects such as dislocation, thickened the surface oxide film, which enhanced corrosion resistance of aluminum wire. Shot peening treatment eliminated aluminum conductor’s original texture, refined the grain, greatly improved the original condition that surface corrosive pitting is easy to grow deeper. To combine those two process, the grains of aluminum got refinement and homogenization, grain distortion energy and dislocation distortion energy were greatly reduced, at the same time the oxide film was thickened, leading to the protection of matrix enhanced. So shot peening+pre-oxidation process is an effective method to improve the aluminum wire’s corrosion resistance.