Adhesion, bonding and mechanical properties of Mo doped diamond/Al (Cu) interfaces: a first principles study

Abstract Diamond reinforced metal matrix composites are considered as a promising thermal management material. The interface between diamond and metal matrix determines the properties of the material to some extent. In this paper, the atomic structure, work of adhesion and binding characteristics of diamond (111)/Al (Cu) (111) clean interface are studied using first principles calculations. The influence of Mo doping on the interface interactions, tensile properties and thermal conductivity of the diamond (111)/Al (Cu) (111) interface is discussed. It is revealed that the work of adhesion of diamond/Al is much higher than that of diamond/Cu interface and the magnetic moments also prove this point of view. Mo doping increases the binding of diamond/Al interface and diamond/Cu interface, with an increase rate of 7.2% and 28.4%, respectively. The tensile strength is decreased due to the Mo doping, but the breaking elongation of diamond/Al (Cu) composites is effectively improved, which is intimately related to the charge density distribution and the localization of density states at the Fermi level. Furthermore, Mo is a good additive element to improve the thermal conductivity of diamond/Cu interface, which gives an interpretation of the reported experimental results through the view of the atomic and electronic structures.