Interfacial properties and electronic structure of beta-SiC(111)/alpha-Ti(0001): A first principle study

First-principles calculations of β-SiC(111)/α-Ti(0001) interface have been performed and the adhesion strength, interface energy, interfacial fracture toughness, and electronic structure are obtained. Six C-terminated β-SiC(111)/α-Ti(0001) interface models are investigated to clarify the influence of stacking sites and Ti atoms tilt direction on the interface bonding and fracture toughness. The hollow-site-stacked interfaces, in which Ti atoms locate on the hollow site of interfacial C atoms (cases III and IV), are more thermodynamically stable with larger work of adhesion, and interfacial fracture toughness. The center-site-stacked (cases I and II) and top-site-stacked (cases V and VI) interfaces have a decreasing interface adhesion as the order. The electronic structure of hollow-site-stacked interface (case IV) gives the evidence that atomic bonding exists between interfacial C, Si, and Ti atoms, and the C-Ti bonds exhibit more covalent features than Si-Ti. The tilt direction of Ti atoms, namely the stacking style of Ti, has a subtle and secondary effect on the interface stability.