**4. Graphene as a reinforcement**

Since 2004, graphene is treated as one of the most wonderful achievements in the field of science and technology Graphene is an attractive alternative to other carbon nanofillers (CNT, CNF, etc.). From the mechanical point of view surface engineering is also meant to be considered an attractive instrument for tribological challenges, several solutions involving chemical, structural and morphological modification by means of adding graphene on surface topography, can be adopted with the aim of improving performances, reducing friction and wear, and/or increasing hardness and toughness [15]. Latest trend has shown that texturing the surfaces of cutting tools can have a beneficial influence on the tribological properties when cutting different types of materials [16]. Moreover, surface textures can act as reservoirs for cutting fluid and increase the fluid's retention on the tool surface leading to enhanced lubrication and cooling. Surface texturing includes modifications of exterior geography, making a uniform smaller scale help with consistently formed severities or depressions. Latest research has considered an advancement of small-scale dimples for automobile portions including bearing and cylinder rings. This examination highlighted the significance of different examples and its impact on decreasing the friction coefficient [17].

Graphene is a novel material in today's scientific world and possesses some excellent properties, such as large specific area, two-dimensional high aspect ratio sheet geometry, and outstanding mechanical, electrical, and thermal properties [18]. The hexagonal crystalline single layer of graphite (the simplest form and one of the most important crystalline allotropes of carbon atoms having a C∙C bond distance of 0.142 nm) has received massive attention in the field of sensors, bio-medicals, composite materials and microelectronics. Thus, graphene is the strongest and best conductive material [19]. Graphene platelets or multi-layer graphene has been used as toughening additives to enhance the mechanical properties of various cutting tool materials [20]. Graphene and carbon nanotubes have attracted much attention in recent years due to their extremely high thermal conductivity, strength and exceptional tribological behavior. Graphene possesses similar mechanical properties as CNTs but has superior electrical and thermal properties, and a larger surface area (2620 m2 /g) [21] because of its 2-dimensional crystal structure. High strength, high thermal properties, and tribological behavior make graphene a good candidate as a reinforcement material for MMCs. Still, study of WC-Co-based cutting tool material made by graphene powder is quite a few **Table 1**.


**Table 1.**

*The properties of multilayer graphene used as reinforcement.*
