Carbon fiber reinforced aluminium matrix composites (CF/Al) are recently used in lightweight applications. In
this study, two groups of composites are fabricated from 0,5,10, 15 &20 wt% CF. One of them is prepared from
12 wt% nano copper (Cu) coated CF and the other is from the uncoated ones. Composites are manufactured by a
hot coining technique through mixing the Al powders with CF using ball milling at 250 rpm, following by hot
compaction under 700 MPa at 500◦C. The effect of reinforcement weight fraction and surface modification on the
microstructure and mechanical properties of CF/Al are investigated. SEM images revealed that the Cu-coated CF
samples have lower porosity and higher homogenization than the other non-coated ones. XRD pattern indicates
the absence of the undesirable Al4C3 phase in two groups of samples. The microhardness and wear properties of
the uncoated CF/Al are significantly improved up to 10 wt % CF. While the ultimate compressive strength value
decreased from 320.8 MPa for the pure Al sample to 179.8 MPa for 20 wt % uncoated CF. Cu-coated CF/Al
composites showed a higher improvement in the mechanical properties compared with the uncoated composites.
The highest reduction percentage between uncoated and coated composites in the wear rate test was about
68.5%. While, the highest increasing percentage recorded in microhardness and compression test were 31.6%
and 23.44%, respectively. The results indicated that surface modification of CF could improve the microstructure
and mechanical properties of CF/Al composites. |
