Study Of Structure Properties And Metal Mold Design Of Aluminum-bronze Collector Shoe

Subway is one of the best approaches to solve the problem of modern urban traffic jam. Collector shoe is the most important component of electric locomotive, which provides power to locomotive by conductor rail. So it's influential on safety and operational costs.Copper base friction materials have been widely using in collector shoe at domestic and abroad. Four kinds of aluminum bronze alloys, which will be strengthened by various heat treatments, had been selected as the research objects for investigation in this paper. Casting technique, microstructure, mechanical properties, conductivity and frictional wear behavior of the alloys had been studied using the methods of numerical simulation and experimental observations.According to the results of the investigation, alloys'structures have been improved and refined by adding Fe (3-4.5%) and RE (0.4%). Hardness of Alloy 3 have been enhanced when 0.4% Be was added, while conductivity significantly reduced. A new phase (k phase) formed in alloy 4 when 4.0% Fe and 4.0% Ni had been added at the same time, which would sprecipitate small granular to strengthening matrix alloys after aging heat treatment.The results indicated that Solution and aging treatment can significantly improve plasticity of alloy 3 and alloy 4, while the strength; hardness remained in the quenched level. Extending the aging time can effectively enhance the alloy's mechanical properties, but the longer the aging time the higher the electric resistance of alloys. According to the results, mechanical properties of the alloy 3 can be improved remarkably by solution treatment at 950℃for 2 h followed by aging at 350℃for 2 h, and dry quenching. While the most suitable heat treatment for the alloy 4 was solution treatment at 950℃for 2 h followed by aging at 450℃for 2 h, and dry quenching.According to the results of wear behaviors, the alloy 3 showed higher anti-friction and wear properties after aging treatment at 950℃×2h,water quenched, aging 2h at 350℃. The alloy 4 followed at 950℃×2h,water quenched, aging 6 h at 450℃. The wear loss and friction coefficient of alloy 2 were higher than that of alloy 3and 4 in all conditions.Shrinkage cavity and shrinkage porosity may appear during the production process. In this study, the casting technique had been optimized by the View Cast software. In order to eliminate the defects that results of original technique, permanent mould casting were used to optimization the technique. Simulation results show that new technology would eliminate the defects. Finally, 3D mold design of the new permanent mould casting system based on Pro/Engineer had been done in this paper.