04.01.2021 •

Reinforcing the Near Eutectic Aluminum–Silicon Alloy with Graphene: An Approach toward Self‐Lubricating Composite


Mechanical and physical properties of aluminum alloys make them suitable for automotive and other structural applications. The high silicon content in aluminum improves the hardness to a great extent but at the cost of ductility. Herein, the reinforcement of near eutectic Al–Si (ADC12) alloy with the reduced graphene oxide (rGO) is demonstrated. The ADC12 alloy and its composite with rGO are cast using the gravity stir die‐casting process. The structural, mechanical, metallurgical, and tribological characteristics are conducted to understand the role of rGO as a reinforcement phase. The 0.7 wt% rGO as a reinforcement phase to ADC12 alloy reduces the friction and wear volume by 50% and ≈90%, respectively, whereas it improves the hardness by 27%. The high‐resolution transmission electron microscopy (TEM) image reveals the wrapping of microstructural silicon by rGO, which inhibits the growth of primary silicon and improves the interfacial strengthening. The high mechanical strength and low shearing properties of rGO, uniform dispersion in the ADC12 alloy, and restrained growth of primary silicon make the ADC12 alloy‐based composites potential materials for structural and low‐frictional building blocks in a diversified range of applications.