On the wear behavior of AA6061 alloy and in-situ AA6061-TiB2 composite subjected to Equal Channel Angular Pressing

Abstract

This paper reports the effect of annealing and Equal Channel Angular Pressing (ECAP) on the wear behavior of AA6061 alloy and in situ AA6061-5 wt.%TiB2 composite. The in situ AA6061-5 wt.%TiB2 composite was prepared through aluminothermic reduction reaction process using potassium hexafluorotitanate (K2TiF6) and potassium tetrafluoroborate (KBF4) salts as precursors in an AA6061 alloy melt. The in situ AA6061-5 wt.%TiB2 composite and AA6061 alloy were subjected to annealing followed by the ECAP process to refine the grain structure. The wear test was carried out on both the materials (AA6061 alloy and in situ AA6061-5 wt.%TiB2 composite) in annealed and ECAP processed conditions using steel as a counter face material. The wear testing was carried out for different wear process parameters like load (20, 30 and 40 N), sliding velocity (0.5, 1, and 1.5 m s−1) and test temperature (25 °C, 100 °C and 200 °C). The ECAP processed AA6061 alloy displayed superior wear resistance than the ECAP processed AA6061-5 wt.%TiB2 composite. The AA6061 alloy subjected to 6 passes exhibited the highest wear resistance at room temperature (25 °C) for the applied load 30 N with a sliding velocity of 0.5 m s−1. Shallow grooves and a slight plough appeared on the worn surface of the AA6061 alloy. The AA6061-5 wt.%TiB2 composite showed ultra-mild wear mode. The Analysis of Variance (ANOVA) test results helped to identify the contribution of every factor to the wear behavior of both the materials. In the AA6061 alloy and AA6061-5 wt.%TiB2 composite, the number of passes and the applied load were respectively the most influencing factors.