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The bow net system is important to the power transmission system of the electric locomotive, the pantograph slide and the contact line is a pair of typical carrier Friction vice poor, the state of contact between the friction pair offline arc is formed, generation of the arc will not only destruction and degradation by the flow state, will accelerate the severe wear of the material, and even endanger the operational safety of the locomotive. Many factors, such as surface roughness, friction pair materials, lubrication conditions, method to pressure, current density, and sliding speed on the friction and wear of the carrier arc generation have an important impact. With the constant speed of the train, the the Offline arc frequency will significantly increase contact Vice surface due to wear and ablation inevitably lead to different roughness, so study the surface roughness of the carbon / copper friction Vice carrier friction and wear bow Internetwork The relationship between significance. Was transformed CETR UMT-2 multifunctional friction and wear testing machine, using the ring - block-contact, friction and wear testing of different roughness and different parameters of the carbon / copper contact Vice carrier, and to study its arc characteristics study the effect of the main results obtained are as follows: 1) the impact of the rougher surface: the presence of larger size contact rough convex peak, so that the real contact area is reduced, leading to the assumed current density increased, the arc starting easier, arc ablation is the main reason for the friction coefficient of the large fluctuations and increase of the amount of wear. Reduce the surface roughness, the frequency and intensity of the arc generated by the arc can be reduced, and reduced wear. 2), when no current is, the coefficient of friction with the normal increase of the pressure is reduced and gradually stabilized, the coefficient of friction when the charging are greater than the friction coefficients of the non-charged, and to increase the coefficient of friction as the current increases. 3) method to the pressure is an important factor affecting the friction process of the carrier whether arcing. Fixing surface roughness under the conditions, there is a critical method to the pressure, greater than the critical value, will not produce a visible arc the friction system stability of the carrier, voltage and current are constant, the wear mechanism of the carbon material is abrasive wear and adhesive wear mainly; less than this critical value, contact Vice arc will be observed between contact with a sharp increase in the voltage between the vice, but the sharp decline in the current sharp rise in temperature, making the material increased wear and tear the carbon materials wear mechanism is abrasive wear, adhesive wear, oxidation wear, of arc ablation and material transfer.
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