TiB₂/Al 复合材料摩擦行为研究

30vol%TiB₂/Al composites were fabricated by squeeze casting technology, and its self-lubricating characteristics under low load and high speed were found. Therefore, the influence of load, sliding velocity and friction pair on the friction behavior of the material was studied by friction tests. The results show that under low load and high speed, TiB2/Al composite and GCr15 bearing steel are under dry friction at room temperature, with the extension of sliding time, the average friction coefficient does not show obviously increasing or decreasing phenomenon, only the instantaneous friction coefficient presents different degree of turbulent fluctuation. In addition, At sliding velocity of 0.8 m/s, with the increase of the load, the average friction coefficient of TiB₂/Al composite with GCr15 is basically unchanged, but the fluctuation amplitude of the instantaneous friction coefficient decreases, and the standard deviation of is friction coefficient decreases. While at 0.49 N, the average friction coefficient does not change significantly with the increase of sliding velocity, fluctuating between 0.165~0.255. The friction coefficient dispersion of TiB₂/Al composites under constant load and variable velocity is higher than that under constant velocity and variable load. When GCr15 is used as friction pair, the turbulent fluctuation of instantaneous friction coefficient is larger than that of composite itself. The average friction coefficient of composites is stable at about 0.08. When grinding with GCr15, the average friction coefficient is stable at about 0.18.