Study on abrasive and erosive wear behaviour of Al 6063/TiB 2in situ composites

Abstract

In the present experimental investigation, Al 6063– xTiB 2 [ x = 0, 5, and10 weight percentage (wt.%)] in situ composites have been prepared by the reaction of mixture of K 2TiF 6 and KBF 4 with molten Al alloy at a reaction temperature of 850 °C. The wear characteristics of the composite in the as-cast conditions were studied by conducting abrasive wear test, and slurry erosive test. The abrasive wear behaviour of the metal matrix composites (MMCs) were investigated by varying parameters like wt.% of TiB 2 particles and load. Dry Sand Rubber Wheel Abrasive Wear (as per ASTM G65 standard) testing machine was used for investigating abrasive wear behaviour. It is evident from the experiments, that in situ formed TiB 2 particles offer effective coverage to the matrix and restrict the metal removal by abrasive particles. In slurry erosion, wt.% of TiB 2, distance traversed and time was used as variables. The results indicate that the wear resistance of TiB 2-reinforced material increased with increase in TiB 2 content. The overall results reveal that TiB 2 particles markedly improve the wear performance of Al 6063 alloy. The surface morphologies of the worn out surfaces were analyzed using SEM. In case of abrasive studies, the mechanism appears to be a mix-up of micro-cutting, ploughing and grain pull-out, while for erosion it is found mainly due to plastic deformation and voids.