Study On Friction And Wear Behavior Of 1Cr18Ni9Ti/Copper-Impregnated Metallized Carbon With Electric Current

With an increase of the operation speed and loading capacity of railway trains, higher quality performances of power supply systems are required. Among these performances, the friction and wear behavior of the contact wires against the current collectors (pantograph strips) with electric currents is worthy of attention. Therefore, carrying out the research of friction and wear with electric current would be of significance for producing enormous economic benefits and promoting the development of the railway transportations.Friction and wear behavior of lCr18Ni9Ti/copper-impregnated metallized carbon with electric current had been studied on a pin-on-disc test rig. During the test, the friction coefficient and wear volume loss were collected. Worn morphology of the specimens was observed by means of an Optical Microscopy (OM), a Confocal Laser Scanning Microscopy (CLSM) and SEM. The effects of normal load, sliding speed, electric current, test environment and power supply pole on behavior of friction and wear were studied. The following results were obtained.1. When the normal load was lower, the friction coefficient of lCrl8Ni9Ti /copper-impregnated metallized carbon was lower, and the specimen was ablated seriously by arc discharge that leaded to an increase of the wear rate of copper-impregnated metallized carbon. When the normal load was higher, the friction coefficient was higher and the wear rate was lower.2. When the normal load was set to 40N, the friction coefficient decreased with the sliding speed increasing. In the condition, the wear rate of copper-impregnated metallized carbon was largest at a sliding speed of 80km/h. When the normal load was set to 60N or 80N, the wear rate increased with the sliding speed increasing. In the case, the friction coefficient reached its maximum value when the sliding speed was 80km/h.3. The electric current has a significant effect on the friction and wear behavior of 1Cr18Ni9Ti/copper-impregnated metallized carbon. With the electric current increasing from 60A to 80A, the friction coefficient was decreased. However, when the electric current was increased from 80A to 100A, it was increased. The wear rate of copper-impregnated metallized carbon increased with the electric current.4. The friction coefficient of lCrl8Ni9Ti /copper-impregnated metallized carbon was higher in a nitrogen environment than in an air environment. The copper-impregnated metallized carbon was ablated seriously by arc discharge and its wear rate was higher in the air environment.5. In the nitrogen environment, the friction coefficient when the copper-impregnated metallized carbon was linked to anode was lower than when it was linked to cathode. However, in the closed air environment the result was quite the contrary.