Amorphous phase stability of NbTiAlSiNx high-entropy films

摘要

In this study,high-entropy films with the composition of NbTiAlSiNx were prepared by a reactive direct current(DC) magnetron sputtering technique,with different nitrogen flow rates(0,4 and 8 ml·min^(-1)).The microstructures and properties were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),high-resolution transmission electron microscopy(HRTEM),nano-indenter and spectrophotometer.All of the as-deposited NbTiAlSiN_X films are shown to have an amorphous structure,and the films exhibit high thermal stability up to 700 ℃.The maximum hardness and modulus values of the films reach 20.5 GPa(4 ml·min^(-1)) and 206.8 GPa(0 ml·min^(-1)),respectively.The films exhibit high absorption of the solar energy in the wavelength of 0.3-2.5 μm,which indicates that NbTiAlSiN_X nitride film is a potential candidate solar selective absorbing coating for high-temperature photo-thermal conversion in the concentrated solar power project.