Effects Of Service And Organization Factors On Damage Behavior Of High-speed Wheel Materials

At present,China's railway is developing rapidly,and the safety of high-speed rail is becoming more and more important.High-speed wheels will experience rolling contact fatigue wear and three-body abrasive wear during service.These damages will reduce the service life of high-speed wheels and affect the safety and comfort of driving.In order to solve the problems that may be faced during the service of different high-speed wheels under different working conditions,this paper studied three domestic high-speed wheel steels with different original organizations,using the MMS-2A contact fatigue wear test machine and MLS-225 dry rubber wheel grinding The particle wear test machine carried out rolling contact fatigue wear test and three-body abrasive wear test,and used optical microscope,micro hardness tester,scanning electron microscope,nano indenter and other methods to wear three high-speed wheel steel morphology,The surface structure evolution and damage behavior were compared and analyzed.The damage behavior of the wheel materials during the rolling contact fatigue and three-body abrasive wear was analyzed from the perspective of microstructure.The service life of the three wheel materials was evaluated.In the rolling-slip contact fatigue wear test,the evolution of the structure morphology of the three steel wear interfaces from the outside to the inside is basically the same.It is found that there is a certain white layer structure,and it varies with the depth from the wear surface.The micro-hardness and nano-indentation hardness of the surface structure were tested.The hardness distribution of the surface structure of the three steels showed a clear downward trend from the outermost layer to the inner region.Through analysis,the two types of bainite steel are more resistant to wear than pearlite steel,and pearlite steel is superior in fatigue resistance,and carbide-free bainite steel has the worst performance in fatigue resistance.In terms of service life,bainite steel performs better than pearlite steel and carbide-free bainite steel.In the abrasive wear test,the amount of wear of carbide-free bainite steel is the smallest,bainite steel is relatively close to it,and pearlite is the largest.The wear mechanism of the three kinds of steel is mainly abrasive wear.The surface of the two types of bainite steel is mainly furrows with different lengths and directions,and is accompanied by a certain amount of spalling and cracks.There are obvious cutting marks.The furrows with different depths and widths along the wear direction are mainly accompanied by a certain amount of spalling and pitting.Therefore,the wear resistance of carbide-free bainite steel among the three high-speed wheel steels is best for long service life,pearlite is the worst,and bainite is centered.