Eur. Phys. J. Plus (2014) 129: 117
https://doi.org/10.1140/epjp/i2014-14117-0

Regular Article

The effect of nitrogen ion implantation on the corrosion resistance and microstructure of tantalum-coated stainless steel

¹ Department of Materials engineering, Tehran Science and Research Branch, Islamic Azad University, Tehran, Iran
² Plasma Physics Research Center, Tehran Science and Research Branch, Islamic Azad University, Tehran, Iran
³ Department of Physics, University of Kashan, Kashan, Iran

^* e-mail: sima.eshghi@srbiau.ac.ir

Received: 9 February 2014
Revised: 20 April 2014
Accepted: 29 April 2014
Published online: 13 June 2014

Abstract

In this work, the effects of nitrogen ion implantation on the corrosion resistance and microstructure of DC magnetron sputtered tantalum-coated stainless steel were investigated. The nitrogen fluence was varied between 3–10 × 10¹⁷ ions/cm² while the beam energy was kept constant at 30 keV. The effects of ion implantation were characterized by X-ray diffraction pattern, atomic force microscopy, and potentiodynamic corrosion test in a 0.5 MH₂SO₄ solution. The atomic force microscopy micrographs were quantitatively and statistically analyzed by computing the multifractal spectrum of the atomic force microscopy images. The results showed that the fluence variation strongly affected the surface roughness and formation of TaN and Ta₂N phases. Increasing the nitrogen fluence up to 10 × 10¹⁷ ions/cm² increased surface roughness. The highest corrosion resistance was obtained at 7 × 10¹⁷ ions/cm² nitrogen fluence.