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241Nanostructured carbon materials and, above all, carbon nanotubes (CNT) have not only been inten sively studied in recent years, but they have also found practical application in the fabrication of electrodes, a variety of sensors, autoelectron emitters, and in the creation of X ray sources that use CNT autoelectron emission [1,2]. In these cases it is often necessary to grow nanotubes directly on the conducting (metallic) substrate. Iron based alloys, including different steels, are very promising for application as substrates. In the latter case this is due to the high iron and carbon con tent in them. The growth of a CNT layer directly on the metallic substrate should increase its adhesion and provide higher electro and thermal conductivity of the "CNT layer-substrate" interface. However, the synthesis of a CNT on a solid substrate is more difficult in comparison with obtaining a CNT on an insulator with a deposited thin film metallic catalyst. This is due to the high mobility and deficiency of localized carbon atoms on the metal surface, and also to the complexity of catalyst island formation because of interaction between the catalytic layer and the metal at high tem peratures typical for CNT growth.It was earlier reported that CNTs were obtained on stainless steel substrates by the thermal decomposition of C 2 H 2 without using an additional catalyst [3]. In this case nanosize granulated structures, being active regions for CNT growth, are formed on the surface due to chemical etching and subsequent thermal treat ment of the substrates at a temperature that stimulates the recrystallization processes. Random orientation of the grown multi layer CNT is typical for such a method. It was shown in [4] that it is possible to obtain a CNT on solid substrates by the plasma enhanced chemical vapor deposition (PECVD) method with preliminary processing of the sample surface in high frequency plasma. The authors suppose that this leads to an increase in the roughness and to the formation of metallic particles on the substrate enabling catalytic growth. The formation of inhomogeneities and differ ent sized particles (including on the nanosize scale) on the metallic substrate also occurs in the case of power ful ion beam (PIB) action [5].This work is aimed at studying the formation of carbon layers on steels, preliminarily subjected to irra diation by a powerful ion beam of nanosecond dura tion, in order to clarify the effect of such processing on CNT growth.Steels with different carbon contents in their com position were used as samples: 12KhN3A (0.09-0.16% C), St3 (0.14-0.22% C), St20 (0.17-0.24% C), St45 (0.42-0.5% C). They were shaped as disks with the diameter 12 mm and thickness 2 mm. Sample preparation included mechanical grinding and polish ing. Irradiation was performed on a Temp accelerator by a proton-carbon (30% H + + 70% C + ) beam with the average energy 300 keV, duration 60 ns, in the cur rent density range 30-150 A/cm 2 with a variation in the number of irradiation pulses from one to five. A planar magn...

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