Stability Of Friction And Effect Of Electric Arc Ablation

The stability of friction with or without current-carrying and its effect of current-carrying wear of highly pure Ti₃AlC₂ bulk and C bulk against low carbon steel has been investigated. Experiments are performed on a block-on-disk type friction tester with sliding speeds from 20-60m/s, pressures from 0.4-0.8MPa and electric current of 2A/mm².The results show:1. Involved in the experimental conditions, the friction coefficient of Ti₃AlC₂ materials and carbon-based materials during the entire experiment with or without current-carrying demonstrate the stochastic volatility, and the relatively stable period, subject to normal distribution. Its standard deviations with the normal pressure, sliding speed and load current changes are different. More stable of friction that is, fluctuations of the smaller, the smaller value of its standard deviation; the other hand the greater.2. The stability of friction and wear rate of Ti₃AlC₂ and C bulk was only slightly affected by the changes of sliding speed and normal pressure in the conditions that without current. However, it causes a significant impact in the current-carrying conditions. The stability of friction decreases with increasing sliding speed or decreasing normal pressure, higher stability corresponds to lower wear rate under current-carrying friction. Standard deviations of kinetic friction coefficients, as a characterization of stability, show strong linear correlation with the wear rate. However, when the sliding speeds are higher than about 50m/s or normal pressures are less than about 0.5MPa, the current-carrier wear rate of Ti₃AlC₂ increases rapidly.3. The stability of friction with or without current-carrying is the main effect factor of current-carrying wear of highly pure Ti₃AlC₂ bulk and C bulk against low carbon steel. Especially under the conditions with current, the enhanced stability can effectively inhibit the process of current-carrying friction micro-arc production, reduce the overall wear rate of materials; the weakening of the stability of the process led to friction and wear surface materials have a micro-arc, larger role in arc ablation, the overall increase in the wear rate of materials.4. Compared to carbon-based materials, Ti₃AlC₂ materials show an excellent stability of with or without current-carrying sliding friction, which determines the Ti₃AlC₂ good friction and wear characteristics. It is good for sliding friction materials with or without current-carrying friction.