Microstructural, mechanical, and sliding wear characterization of an Al90Cu4Fe2Cr4 spray-formed alloy

Abstract

In this work, the microstructure and sliding wear behavior of a spray-formed Al90Cu4Fe2Cr4 (at%) alloy was studied. Mechanical properties under compression and Vickers microhardness were also evaluated. The microstructure of the spray-formed material consisted of an α-Al matrix reinforced with two complex intermetallic phases, λ-Al13Fe4 and Al13Cr2, which are binary based intermetallic structures, with significant amounts of the other elements of the alloy. The dry-sliding wear resistance of the composites was evaluated using a pin-on-disk test configuration, with normal loads ranging from 10 to 20 N and sliding velocities of 0.05–0.2 m.s−1. Alumina spheres were used as counter-bodies in these tests. The samples exhibited a high sliding wear resistance and showed almost no variation in the specific wear rates for all test parameters used, with values ranging from 7×10−4 to 8×10−4 mm3/N.m. The coefficient of friction also remained almost constant, around 0.4, and the main wear mechanism was the delamination of intermetallic particles. The results indicate an improved dry-sliding wear resistance at high normal loads compared to previously fabricated Al-matrix composites reinforced with quasicrystals and complex intermetallic phases. The mechanical properties of this alloy, fabricated in a single-step process, was in the same range as found for previous studies, of Al-matrix reinforced with micron-sized quasicrystals and intermetallics, prepared by more complex processing techniques. The simplicity of the one-step preparation process used in this study contributes to the development of more efficient and cost-effective tribological materials for various applications.