**Author details**

Prashantha Kumar H.G.\* and Anthony Xavior M.

\*Address all correspondence to: prashanthakumar.hg@gmail.com

School of Mechanical Engineering, VIT University, Vellore, Tamil Nadu, India

#### **References**

**6. Conclusion**

Graphene + SiC (d) Aluminum + Graphene + Al<sup>2</sup>

168 Graphene Materials - Structure, Properties and Modifications

and friction. Addition of graphene in SiC/Al<sup>2</sup>

One of the common engineering research challenges in materials is to determine ways and means to improve the wear resistance between any coupling surfaces, thereby reducing the energy and wear losses. In the current research work, aluminum with graphene is processed separately through vacuum hot press (gives high improved density compacts >98%) followed by microwave sintering successfully. Addition of graphene will provide more number of nucleation's regions. Aluminum-graphene composites are observed to be superior in hardness compared to monolithic material owing to uniform dispersion and higher dispersion strengthening mechanism. Graphene exhibits more grain refinement, which improves the fracture toughness of the composite. This feature has reduced wear losses, and therefore, graphene-reinforced composites are suitable for various tribological applications. The significant differences in the friction coefficients due to high protective nature of graphene will lower the shear force and reduce the material losses. Further, graphene and MWCNT combinations in composite become a sacrificial layer which smeared (dry lubricant) on the wearing surface and enable the self-lubricating properties of aluminumgraphene/MWCNT composites. Graphene/MWCNT (flattened–ball-milled) combination is a favorable tribological application, coupled with improved hardness, strength, and surface roughness values compared to individual MWCNT or graphene/MWCNT (tubular) reinforced aluminum composites applications, where the component is exposed to wear

**Figure 12.** Optical micrographs of worn-out surface of (a) Aluminium (b) Aluminum + Graphene, (c) Aluminum +

(e) Aluminum + Graphene + Al<sup>2</sup>

O3 + SiC.

O3

O3

improvement in hardness compared to base aluminum. Microwave sintering method can

and encapsulation enables significant


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