Synergistic effects of AlB₂ and fluorinated graphite on the mechanical and tribological properties of hybrid fabric composites

In present work, the dry sliding wear properties of hybrid PTFE/Nomex fabric/phenolic composite (hybrid fabric composite), filled with aluminum diboride (AlB₂), fluorinated graphite (FGr), and simultaneously filled with above fillers were investigated using a pin-on-disc tribo-meter. The wear rate and friction coefficient of hybrid fabric composite reinforced by different fillers were determined. Besides, the effects of fillers on hardness, thermal stability, thermal conductivity of hybrid fabric composites were systemically studied. The results showed that 3 wt% AlB₂ filled hybrid fabric composite exhibited excellent anti-wear properties. The optimal filler percentage was determined by changing the content of FGr from 2 to 8 wt% whereas AlB₂ was kept constant at 3 wt%. Those results mainly attributed to the improved hardness, thermal stability and thermal conductivity of hybrid fabric composite. Furthermore, the transfer film formed on the counterpart pin surfaces was demonstrated to be efficient in enhancing the tribological properties of filler reinforced hybrid fabric composites. The worn surfaces of the hybrid fabric composites were studied by scanning electron microscopy (SEM) and the corresponding wear mechanisms were discussed based on the characterizations.