First principles calculations of interfacial adhesion energy between Fe substrate and transition layer of films

Transition metal nitride films have high hardness and low wear rate, but the film substrate bonding strength between the film and the Fe substrate determines whether the film is useable. Adding transition layer materials is an effective way to improve the bonding strength of the membrane substrate. This article selects Ti, Zr, Hf, V, Cr, Ta, and TiN as transition layer materials, and uses first principles to calculate the interface bonding energies of ten interface models: Fe/TaN, Fe/Cr, Fe/V, Fe/Ti, Fe/Zr, Fe/Hf, Fe/Ta, Fe/TiN, Ti/TiN, and TiN/TaN. The model with higher bonding energy is selected to calculate the atomic population, electron gain and loss, and partial wave density of states of atoms, and further study the bonding situation at the interface. By comparing the bonding energy, the interfacial bonding energy between Fe and transition layer materials Ti, V, Cr, Ta, and TiN is higher than that of Fe and TaN films. And the interfacial binding energy of Fe/Ti, Ti/TiN and TiN/TaN are 0.3041eV/Å2, 0.4217eV/Å2 and 0.3687eV/Å2, respectively, which are higher than that of Fe and TaN film. Therefore, when preparing TaN thin films on Fe substrates, adding a double transition layer material Ti/TiN between the Fe substrate and TaN thin films, forming an interface model with a four layer structure of Fe/Ti/TiN/TaN, can optimize the bonding force between the substrate and the film to the greatest extent. •The interfacial bonding energy between various transition layer materials and iron substrates has been theoretically calculated for the first time.•The calculation results show that there is a large interface Binding energy between Ti, V, Cr, Ta, TiN and Fe substrate.•Adding Ti/TiN double transition layer material between Fe substrate and TaN film can maximize the adhesion between the film and substrate.