Fabrication and Characterization of Aluminum-Graphene Nano-Platelets—Nano-Sized Al4C3 Composite

Abstract

Reinforcement of aluminum and aluminum alloys with graphene has been intensively practiced by researchers in the past dozen years. The role of Al4C3, which could be produced unintentionally or purposefully during the composite production, was controversial until it was found that nano-sized carbides were beneficial for strengthening the composites. aluminum-graphene-nano-sized Al4C3 composites were produced by us using the powder metallurgical method and subsequent annealing. The microstructure was investigated using light microscopy (LM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), transmission electron microscopy (TEM), and high resolution transmission electron microscopy HRTEM. Nano-sized carbides were found at the interface aluminum-graphene. The formation of a chemical bond between aluminum and graphene during annealing was proved. Lower values of the microhardness and strength characteristics of the composites after extrusion and subsequent annealing during which nano-sized carbides are formed were found in comparison with those obtained after extrusion. It could be supposed that the annealing processes contribute more to the reduction in microhardness and strength characteristics than nano-sized carbides contribute to its increase. The presence of a strong chemical bond between the graphene and the aluminum is manifested in the failure pattern, which is characterized by graphene nano-platelets and nano-sized carbides fracture and semi-pulled out or semi-slipped Al4C3 from the matrix.

Investigating the Effects of Graphene Nanoplatelets and Al4C3 on the Tribological Performance of Aluminum-Based Nanocomposites

“…The production method was the same as the method described in [16]. -Powder mixing in a planetary agate ball mill.…”

“…Graphene nanoplatelets (GNPs) are one of the most promising reinforcements for aluminum composites due to their exceptional mechanical, electrical, thermal and chemical properties [15]. GNPs consist of a few layers of graphene sheets with a thickness of less than 10 nm and a lateral size of up to several micrometers [16]. GNPs can enhance the mechanical properties of aluminum composites by increasing their stiffness, strength, hardness and ductility.…”

“…The peaks of aluminum, graphene and the amorphous phase are labele G. The peak of graphene corresponds to the (002) plane. The asterisks (*) denote the b aluminum.The small peak at 54° 2θ in the HT sample is a probable trace peak of Al4C3 ( from[16].…”

“…This investigation builds upon a previous study in which Al-based composites reinforced with GNPs were fabricated using the powder metallurgy method, followed by heat treatment. The microstructure, mechanical properties and microhardness of the composites during tensile testing were investigated in the prior study [16].…”

Explanatory Machine Learning Accelerates the Design of Graphene-Reinforced Aluminium Matrix Composites with Superior Performance

“…Mishra et al [12] experimentally investigated the effect of graphene on the wear properties of aluminium alloys and found that graphene can make the microstructure of the material more homogeneous and improve the wear and friction properties. Lazarova et al [13] investigated the effect of annealing heat treatments on aluminium alloys reinforced by graphene nano-sheets, and found that the effect of graphene nanosheets on the strength of aluminium alloys, due to annealing, was greater than that due to the strengthening effect of graphene and carbides. However, the properties of aluminium matrix composites are greatly influenced by both the preparation process and matrix composition.…”