Wear behaviour of AA6061 aluminium alloy and its composites

This study investigates the wear resistance of four AA6061 MMCs together with the monolithic AA6061 alloy, all in the T6 condition, using a pin-on-disc test. In addition to the widely studied 20 vol.% Saffil MMCs, the present investigation considered a hybrid of 11% Saffil + 20% Sic, and a high volume fraction Sic, MMC. AA6061 + 60% Sic,. The wear behaviour against P400 Sic grit adhesive bonded paper and against BS817M40(EN24) steel were explored under an applied load of 9.8 N with a nominal contact pressure of 0.5 MPa. It was found that after testing against Sic grit, AA6061 + Saffil showed little advantage over the monolithic alloy, but the other three composites had a significant improvement in wear resistance. The hybrid and the AA6061 + 60% Sic showed the best performance. Only small improvements were noted for AA6061 + Saffil and AA6061 + 20% Sic over the monolithic alloy, when tested against steel. However, the addition of 11% Saffil to 20% Sic in the hybrid, resulted in this composite and the AA6061 + 60% Sic being retained in regime I of the Alpas and Zhang classification, and recording low wear rates.