Experimental Research On The Friction And Wear Properties Of Rail Material Under Permanent Magnet Field

With the rapid development of railway industry in recent years,railway transport continuously develops in the direction of high speed and overload,accompanying the abrasion of rail become more and more serious,and the intensified abrasion will directly affect the running safety of the train and transportation costs of the railway.Therefore,the study of the problem of rail abrasion,which is based on the research on the characteristics of the friction and abrasion of the rail materiel,is particularly important,and has important economic significance and guiding significance to reduce the abrasion of the rail.This article is based on some existing test equipment,such as high speed reciprocating friction and abrasion testing machine of HSR-2M type.It has studied the influence of some changing factors,such as the normal force,reciprocating velocity,and running time respectively,to the characteristics of the friction and abrasion of the rail material,under the condition of permanent magnetic field and the condition of no magnetic field.The study mainly focuses on the friction coefficient,the wear volume,rate,contours,morphology and mechanism by using XRD scanning to do the phrase analysis.The main findings through the test research are concluded as follows:(1)The introduction of the permanent magnetic field can significantly reduce the parameter of the friction coefficient under the test conditions,the wear volume and rate of the rail material in the test.Permanent magnetic field,reduce the degree of abrasion to some extent.(2)The increase of the normal force under permanent magnetic or non-magnetic environment will reduce the friction coefficient,while increase the wear rate and volume of the rail material to some extent.But with the increase of the force,the increasing trend of the wear volume and rate will slow down,thus the change of the normal force to the characteristics of the friction and wear is not absolute.(3)The increased reciprocating velocity will reduce the friction coefficient of the rail material to some extent under permanent magnetic field and non-magnetic field environment,accompanying a decreasing trend of the wear volume and rate.But with the continuous improvement of reciprocating velocity,the decrease of the wear volume and rate is no longer apparent.Therefore,the reciprocating velocity in the aspect of influencing the features of the friction and wear of the material is not the higher the better,there is a optimal solution.(4)The observation of the morphology of the rail surface of the grinding crack,which is finished by contrasting the observations before and after the experiment under the permanent magnetic field and non-magnetic field environment,shows that the morphology of the grinding crack of the rail surface under the magnetic fields is given priority to mild adhesive abrasion,while the performance under non-magnetic field environment is more characterized by abrasive wear.(5)The permanent magnetic field under the condition of oxidation is more apparent,with better crystallinity by using the XRD spectrum analysis.The magnetic field can affect and promote the oxidation,and the crystallinity of materials,thus will influence the features of friction and abrasion of the material.