The formation of nanosized surface layers the Armco-iron, the stainless steel and the copper by N$^+$ and O$^+$ ion implantation

V. L. Vorobyov, F. Z. Gilmutdinov, P. V. Bykov, V. Ya. Bayankin

Physical-Technical Institute, Ural Branch of the Russian Academy of Sciences, Izhevsk, Russia

Abstract: Service properties of metals and alloys are controlled by the structure-phase state of surface layers, and they can be significantly improved by surface modification. As is known, ion implantation is used as a method of surface treatment of metals and alloys. The most important features of this method, in contrast to other ion-vacuum processing methods, are the minimum changes in object geometrical sizes and the possibility of low temperature processing. However, the use of the ion implantation method is complicated by insufficient knowledge of the relation between implanted ion parameters and ion concentration in solids, as well as the absence of techniques for choosing technological conditions of processing.
Therefore, the objective of this research is to study the formation of nanosized surface layers of metallic materials by ion implantation depending on the chemical activity of the implanted elements to the components of the alloy. The effect of O$^+$ and N$^+$ ion implantation in pulsed mode (f=100 Hz, t=1 ms) with ion energy of 30 keV, current density per pulse of 3 mA/cm$^2$ and irradiation doses 10$^{17}$ and $5\cdot10^{17}$ ion/cm$^2$ on the formation of the nanosized surface layers of the samples of Armco-iron, stainless steel AISI 321 and copper brand M0 has been investigated. The XPS technique examination has shown that accumulation of the nitrogen atoms in nanosized surface layers of the Armco-iron by N$^+$ ion implantation is made up of trace quantities. The N$^+$ ion implantation in the samples of AISI 321 stainless steel leads to the accumulation of nitrogen atoms up to 10 at.% and more. This is due to the presence of stainless steel elements with a chemical affinity to nitrogen atoms. The parameters of irradiation were the same by N$^+$ ions.
It has been shown that the formation of the nanosized surface layers by ion implantation determines by the chemical activity of implanted ions to the component of the alloy.

Keywords: ion implantation, X-ray photoelectron spectroscopy, chemical composition, nanosize surface layers.

UDC: 537.534:539.422.24:620.178.152.34