Effect of graphene on the mechanical and anisotropic thermal properties of Cu–Ta composites.

Strong interfacial bonding is the basic requirement for metal-graphene composites for higher thermo-mechanical properties. In the present work, a novel metal tantalum is introduced in the metal-graphene composites prepared by (ball-milling + molecular level mixing) followed by hot press sintering. SEM, transmission electron microscopy and high transmission electron microscopy are observed to check the interface area which shows the presence of tantalum carbide on the interface area which is formed during the sintering process. The formation of the carbide element significantly enhances the mechanical properties of composites. The addition of a very low amount of 0.1 vol% of rGO give the very high yield strength 200 MPa and ultimate tensile strength value 375 MPa with the good agreement of ductility, Vickers hardness 95 HV and bending strength 617 MPa which are much higher than unreinforced copper–tantalum composites and even from pure copper. The anisotropic thermal conductivity values are also significantly improving due to the better interfacial bonding and the ratio was 5 which is just 1.01 for pure copper. The formation of carbide elements and extraordinary high mechanical values with good ductility and anisotropic thermal conductivity ratio can lead to these materials used in thermal packaging systems and the electronic industry. [ABSTRACT FROM AUTHOR]