Investigation of microstructures and properties of graphene reinforced 20CrMnTi materials

As a member of low-carbon alloy steels, 20CrMnTi has been widely used to manufacture key-parts, such as gears and shafts, owing to its attractive fatigue resistance and easy of processing. To improve its the mechanical and frictional properties, the preparation of composite is required. In the present study, graphene was added in 20CrMnTi to form Gr/20CrMnTi composites by vacuum high-energy ball milling process and hot-pressing technique. The addition of graphene has a profound influence on the microstructure and properties of 20CrMnTi. A high hardness of 5.83 GPa and a good tensile strength of 1183 MPa were obtained in the 0.5 wt.%-Gr/20CrMnTi, increased by 18.5% and 27.8%, respectively. Meanwhile, the wear resistance reaches a maximum value of 2276.5 cm-3 in the 0.7 wt.%-Gr/20CrMnTi, showing a 491.1% increase than that of pure 20CrMnTi. The layered graphene played an important role in absorbing energy and preventing the propagation of micro-crack.