MATERIALS RESEARCH EXPRESS, cilt.6, sa.12, 2019 (SCI-Expanded)
This study addresses the effects of particle volume fraction on the low-velocity impact behavior of B4C particle-reinforced Al6061 metal matrix composites. For this purpose, Al6061 matrix B4C reinforced metal matrix composite materials were produced by powder metallurgy method. Metal matrix composite samples were produced by hot pressing in B4C particle volume fractions of 0, 5, 10 and 15%. Composite samples were subjected to impact using a drop-weight test device in a velocity of 4.55 m s(-1) with 5.045 kg striker. After low-velocity impact tests, samples were cut out for cross-sectional examination and measuring residual central transverse displacements. The results were examined in terms of contact force-time, contact force-displacement, impact energy-time curves as well as residual central transverse displacements. Also, microstructural characterizations before and after the impact tests were performed by the Scanning Electron Microscopy (SEM). It was found that metal matrix composite samples exhibited superior impact energy absorbing capacities than unreinforced material under low-velocity impact conditions. Particle volume fraction had a considerable effect on the impact strength, and thus, the impact energy absorbing capacity in composites improved with increasing the particle volume fraction. While the particle volume fraction increased, the composite structures behaved stiffer. As a result, the peak contact force was increased, and the impact durations were almost decreased. However, Al6061/B4C metal matrix composite materials having 15% volume fraction exhibited best impact performance.