Enhancing surface properties of (Fe,Cr)Al – Al2O3 nanocomposite by oxygen ion implantation

Ion implantation has been used as a surface treatment technique on (Fe,Cr)Al-10%vol Al2O3 nanocomposite to enhance its surface properties. The process was carried out at 150 kV with an oxygen dose of 1 × 1018 ions/cm2 at room temperature. Microstructural characterization and phase composition were performed by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD) of the Al2O3 layer formed on the nanocomposite surface. Mechanical properties measurements including hardness, fracture toughness and coefficient of friction were studied. Nanoindentation tests demonstrated an increase of 50% in the hardness value after ion implantation. Fracture toughness increased to a value of 21.3 ± 0.9 MPa m1/2 after O2 ion implantation. Scratch test results revealed an improvement in tribological behavior of the oxygen implanted surface compared to the un-implanted substrate. Cyclic oxidation tests, at 1100 °C, revealed that oxygen ion implantation slightly improved high temperature oxidation resistance of the nanocomposite. [Display omitted] •A new (Fe,Cr)Al–Al2O3 nanocomposite was prepared by mechanical alloying.•Oxygen ion implantation was performed to enhance surface properties of the nanocomposite.•Increase in elastic modulus and fracture toughness caused improved tribological behavior.•Ion implanted layer of only 100 nm lead to higher oxidation resistance at 1100 °C.