Role of ilmenite particles on high temperature wear behavior and coefficient of friction of LM30 aluminium alloy composites

Abstract

In this study, experimental approach involves material preparation via stir casting, extensive testing, and characterization. Optical microscopy, Scanning Electron Microscopy (SEM), and X-ray Diffraction (XRD) analysis reveal the uniform distribution of ilmenite particles within the alloy matrix and the formation of intermetallic phases. The thermal characteristics analysis demonstrates reduced 29 % coefficient of thermal expansion (CTE) in the composites, in the case of 15 wt% fine ilmenite particles reinforced composite. Hardness tests improvements in hardness, with the 15 wt% (32–50 μm) ilmenite Aluminium Metal Matrix Composite (AMC) exhibiting a 69% increase over the base alloy. Wear testing at various temperatures and loads showed the superior wear resistance of the composites compared to the base alloy, with the C3-15 composite outperforming cast iron typically used in brake drums. The wear rate of LM30 and LM30 + 15 wt% ilmenite (32–50 μm) (C3-15) sample is 38.8671 x 10−4 mm3/m and 10.50768 x 10−4 mm3/m at 200 °C and 68.67 N applied load, respectively. The coefficient of friction analysis further supports the enhanced performance of the composites. The coefficient of friction (COF) of LM30 + 15 wt% ilmenite (32–50 μm) (C3-15) is 0.29898, 0.47645 at 9.81 N and 68.67 N load, respectively measured at a temperature of 200 °C. Examining worn surfaces and debris provides insights into the wear mechanisms, including adhesion and abrasive wear. Overall, this research suggests the potential suitability of ilmenite-reinforced LM30 alloys as alternatives to traditional brake drum materials, offering improved thermal stability and wear resistance.