Adhesion strength, stability and electronic properties of TiB2 reinforced copper matrix composites: A first principles study

Abstract The first principles method was utilized to study the interfacial properties of the TiB2 reinforced copper matrix materials. The interfacial stabilities were studied initially via the works of adhesion and interfacial energies. According to the results, TT-OT (Ti-terminated TiB2/Cu “OT” stacking) and BT-HCP (B-terminated TiB2/Cu “HCP” stacking) were confirmed to be the most stable interfaces. The charge density distribution, charge density difference, electronic localization function and partial density of state were analyzed for TiB2/Cu interfaces. The results indicate that Ti-terminated TiB2(0001)/Cu(111) interfaces were more inclined to form the metallic bond, while the B-terminated TiB2(0001)/Cu(111) interfaces were likely to form the ionic bond. Moreover, the interfacial elastic energy, interfacial fracture toughness and ultimate tensile tress were carried out to make clear of fracture mechanism of the TiB2(0001)/Cu(111) interfaces. The TT-OT and BT-HCP were confirmed to be the two most stable interfaces due to their largest interfacial elastic energies. The computational ultimate tensile tress for Ti-terminated TiB2(0001)/Cu(111) and B-terminated TiB2(0001)/Cu(111) interfacial models were 23 GPa and 25 GPa, respectively.