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

Abstract

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.

Mechanism of Ceramic-Like Friction of Quasicrystal-Reinforced Al Matrix Composites Formed by In Situ Directed Energy Deposition

“…From the static microhardness results, it can be concluded that Al 13 (Fe, Cr) 4 and QC Al 91 Fe 4 Cr 5 could act as the reinforcement phase for this QC/Al composite. [38]. The detailed explanation of these results and the intimacy of the contact is introduced in Sec.…”

Electromagnetic Preparation and Wear Behavior of In Situ Si‐Reinforced Al–Matrix Gradient Self‐Lubricating Composites

“…[8] To improve wear problem of Al-alloy workpieces at high temperatures, developing novel and efficient self-lubricating Al-matrix composites has attracted widespread attention. [9,10] At present, there are two main strategies for designing and preparing self-lubricating Al-matrix composites. One is surface treatment, i.e., depositing solid self-lubricating films on the composite surface by anodizing, [11] microarc oxidation, [12] pulsed laser deposition, [13] electrical discharge alloying, [14] and plasma electrolytic oxidation.…”

“…[ 8 ] To improve wear problem of Al‐alloy workpieces at high temperatures, developing novel and efficient self‐lubricating Al–matrix composites has attracted widespread attention. [ 9,10 ]…”

Natural Aging Effect of Al-20Zn-3Cu Alloy on Mechanical Properties and Its Relation to Microstructural Change

“…Among several Al alloys, ADC12 (Al-Si-Cu) alloy is a conventional cast alloy applied to power train and transmission cases due to its high castability with a low shrinkage rate [7][8][9]. Nevertheless, ADC12 has a brittle nature because of the formation of intermetallic phase containing Si element [7,[10][11][12][13]. Recently, high-Zn Al-based-alloys have attracted much research interest as a promising Al-cast alloy for automotive applications.…”