Tribological performance of LM-26 aluminium matrix composite reinforced with chromium oxide

Abstract The study indicated that LM26 aluminium alloy matrix composites containing Cr₂O₃ particles were successfully fabricated using a stir-casting method. Four sets of samples (S1-S4) were prepared and analysed using scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy-dispersive X-ray spectroscopy (EDX) for compositions of 0, 5, 7.5, and 10 wt% Cr₂O₃, respectively. The microstructural examination of the LM26 matrix confirmed that the Cr₂O₃ particles were uniformly distributed throughout. Compared to the base alloy, the hardness of Sample S4, which contained 10 wt% Cr₂O₃, increased by 35.68%. Investigations into wear behaviour revealed that weight loss increased overall as a function of both sliding speed and load. Nonetheless, Sample S4 demonstrated superior wear resistance, with a weight loss reduction of 41.54%. The better wear resistance seen in Cr₂O₃-reinforced composites is partly due to the creation of a thick oxide layer, which was shown by examining the worn surface. These results suggest that LM26 is an excellent choice for applications requiring strong wear resistance, as the incorporation of 10 wt% Cr₂O₃ reinforcement significantly enhances its hardness and performance in friction-related scenarios.