Influence of precipitation and solution strengthening on abrasive wear resistance

The influence of precipitation and solution strengthening on gouging abrasion resistance has been studied using a 6061 aluminium alloy heat treated to obtain four different microstructures. Single-event abrasive grooves were generated using a modified Charpy impact tester and the specific energy consumption in grooving was recorded and used as a measure of wear resistance. In addition, the mechanisms of chip formation and material removal were studied by metallographic analysis of “quick-stop” specimens.The results of the grooving tests show that for small grooves precipitation strengthening yields higher energy values than solution strengthening, the wear resistance increasing with decreasing precipitate size. The ranking of the different heat treatments with respect to specific grooving energy depends, however, on the considered damage depth and the opposite order of ranking is found at the largest groove depths. On the basis of the results of the grooving tests, a discussion on the influence of groove depth and microstructure on chip formation and specific grooving energy is presented. In particular, the inhomogeneous nature of the plastic deformation involved in chip formation is discussed, and the resulting importance of the thermal stability of the material in determining wear resistance is emphasized.