Study on the significant enhancement in the wear properties of self-lubricant aluminum composite by inclusion of ultra-strength hafnium diboride particles

ABSTRACT

This work focuses on investigating the significant enhancement in wear properties of AA6061 alloy hybrid composite through the inclusion of graphite and hafnium diboride (HfB₂) particles. AA6061 alloy, largely deployed in aviation and automobile sectors because of its high corrosion and in wear resistance. Stir casting method was adopted to create hybrid composites by adding different percentages of graphite and HfB₂ particles into the AA6061 matrix. SEM and Microhardness were used to examine the microstructure of the resultant composites to verify the even dispersal of reinforcing particles and the alloy's hardness. To compare the tribological performance of the hybrid composites to that of the base AA6061 alloy, wear experiments were conducted under different loading conditions. Results revealed a considerable improvement in wear resistance with the inclusion of 5% of graphite particles with 15% of HfB₂ particles. Hard HfB₂ particles improved load-bearing and abrasion resistance. The synergistic effect of graphite and HfB₂ resulted in a hybrid composite with significantly lower wear rates and friction coefficients contrast to the base AA6061 alloy. This work findings highlights the potential of hybrid reinforcement strategies in developing advanced materials with enhanced tribological performance making it promising for suspension components and roof rails in automotive sectors.

Keywords:
Hafnium diboride; Solid lubricant; Tribology, Lightweight aluminum alloy; Wear resistance; worn surface characterization