High-power Ion Beam Research Articles

Synergy of high-intensity chromium ion implantation and ion beam energy impact on the zirconium alloy surface

The peculiarities and modes of material modification with high-intensity, high-power density ion beams on the irradiated surface are studied for the first time. Chromium ions are implanted into a zirconium alloy using a 25 kW/cm2, 450 μs beam at the pulse repetition rates within 8–35 pps. Every high-energy ion pulse impact is followed by ultrafast cooling of the surface due to heat removal into the target material. Three modes are studied at the temperatures of 580, 700, and 900 °C with an additional pulsed heating. An increase in the average target temperature from 580 to 700 °C within 1 h at the same pulse power density allows increasing the depth of chromium ion alloying from 1.5 to more than 7 μm. The use of ultrafast cooling of the Zr1%Nb alloy surface offers a grain size reduction from a few μm to approximately 50–250 nm, without any microstructural changes throughout the sample volume. An inhomogeneous chromium ion distribution over the target surface and depth is observed.

Properties of a High-Power Ion Beam with Particle Energy up to 1 MeV Obtained from a Plasma Created by a High-Voltage Pulse on a Graphite Cathode

Properties of a High-Power Ion Beam with Particle Energy up to 1 MeV Obtained from a Plasma Created by a High-Voltage Pulse on a Graphite Cathode

Analysis of the State of the Surface Layer of the SAP-2 Composite Alloy after Irradiation with a High-Power Ion Beam

Analysis of the State of the Surface Layer of the SAP-2 Composite Alloy after Irradiation with a High-Power Ion Beam

Effects of Laser Pretreatment on the Formation of Nanostructured Carbon on the Surface of Chlorinated Polyvinyl Chloride under High-Power Ion Beam Irradiation

Effects of Laser Pretreatment on the Formation of Nanostructured Carbon on the Surface of Chlorinated Polyvinyl Chloride under High-Power Ion Beam Irradiation

Effects of laser pretreatment on the formation of nanostructured carbon on the surface of chlorinated polyvinyl chloride under high-power ion beam irradiation

The features of formation of surface morphology of chlorinated polyvinyl chloride (pure and with the addition of the catalyst - ferrocene) under the influence of a high-power ion beam of nanosecond duration after the preliminary pulsed laser treatment of the polymer surface have been investigated. It was found that the morphology of the irradiated surface of chlorinated polyvinyl chloride after pulsed laser surface pretreatment differs significantly from the morphology of the irradiated surface of chlorinated polyvinyl chloride after a preliminary stationary heat treatment. For pure chlorinated polyvinyl chloride, pulsed laser pretreatment with increasing power leads to an increase in the porosity of the surface layer after high-power ion beam irradiation, whereas different surface morphologies, including fibers (including polymer fibers) of different diameters, can be obtained for the pre-stationary post-irradiation thermal treatment of this polymer. Pre-stationary thermal pretreatment of chlorinated polyvinyl chloride with the addition of ferrocene (Fe(C5H5)2) leads to a decrease in the diameter of formed carbon nanofibers (with an increase in the treatment temperature). During the pulsed laser pretreatment, an increase in the porosity of the treated layer and a slight increase in the proportion of nanofibers of larger diameter are observed. To explain the obtained differences for pulsed laser and stationary thermal pretreatment, the effect of polymer heating rate on the features of chlorinated polyvinyl chloride decomposition was analyzed.

Features of thermal processes and the influence of pulsed heating of surface layers of titanium on the diffusion transfer of dopants during high-intensity ion implantation

Methods for modification of surface and near-surface layers of materials and coatings by ion beamshave prospects for application in many fields of science and technology. The method of high-intensityimplantation by high-power density ion beams with submillisecond duration involves significantpulsed heating of the irradiated target’s surface layer, followed by its rapid cooling due to heatremoval into the material due to thermal conductivity and the implementation of repetitively-pulsedradiation-enhanced diffusion of atoms to depths significantly exceeding the projective ion range. Thispaper considers features of thermal processes and the effect of pulsed heating of near-surface titaniumlayers on diffusion transfer under conditions of synergy of high-intensity titanium ion implantationand energy impact of a high-power density repetitively-pulsed beam on the surface to increase iondoping depth due to radiation-enhanced diffusion under conditions of limited heating of the entiresample. The paper presents the data of numerical simulation of dynamic changes in temperature fieldsin titanium and titanium self-diffusion under the action of ion beams with a submillisecond durationand a pulse power of tens of kW/cm2 and fluence of ions in a pulse 1.25×1015 ion/cm2.

The Effect of a High-Power Pulsed Ion Beam on the Surface Topography of Tungsten

The Effect of a High-Power Pulsed Ion Beam on the Surface Topography of Tungsten

Longitudinal bunch profile measurement of operational H− beam using laser wire and virtual slit

We propose and demonstrate a nonintrusive diagnostic technique for measuring longitudinal bunch profiles of an operational high-power hydrogen ion (${\mathrm{H}}^{\ensuremath{-}}$) beam in the Spallation Neutron Source (SNS) linear accelerator at Oak Ridge National Laboratory (ORNL). The technique consists of a laser wire formed by a picosecond pulsed laser beam and a virtual slit created by controlling the magnetic field of the electron detector. The virtual slit eliminates the influence of the transverse beam profile and size on the longitudinal bunch profile measurement. The effectiveness of the diagnostics is investigated first in numerical simulations followed by experimental demonstrations performed on the neutron production (1.4 MW on target) ${\mathrm{H}}^{\ensuremath{-}}$ beam at the SNS superconducting linac. The results from the present measurement method are verified by an independent measurement approach.

Features of the Effect of a High-Power Ion Beam of Nanosecond Duration on Polyethylene Terephthalate

Features of the Effect of a High-Power Ion Beam of Nanosecond Duration on Polyethylene Terephthalate

Modification of the Properties of Surface Layers of Aluminum Alloys under the Action of a High-Power Ion Beam

Modification of the Properties of Surface Layers of Aluminum Alloys under the Action of a High-Power Ion Beam

Formation of High-Power Pulsed Titanium Ion Beams of Submillisecond Duration from Vacuum Arc Plasma

Formation of High-Power Pulsed Titanium Ion Beams of Submillisecond Duration from Vacuum Arc Plasma

Modification of the Properties of the Surface Layers of Aluminum Alloys under the Action of a High-Power Ion Beam

Modification of the Properties of the Surface Layers of Aluminum Alloys under the Action of a High-Power Ion Beam

Features of the Effect of a High-Power Ion Beam of Nanosecond Duration on Polyethylene Terephthalate

Features of the Effect of a High-Power Ion Beam of Nanosecond Duration on Polyethylene Terephthalate

Влияние предварительной термической обработки на морфологию углеродного слоя, формирующегося на поверхности хлорированного поливинилхлорида при воздействии мощного ионного пучка

The effect of preliminary heat treatment on the morphology of carbon layer formed on the surface of chlorinated polyvinyl chloride with the addition of ferrocene (10 % of polymer weight) under the impact of a high-power nanosecond-durable ion beam has been studied. Preliminary exposure of samples in an oven at different temperatures for 1 hour leads to partial dehydrochlorination of the surface layer of the polymer film and interchain crosslinking, creating centers for the start of the carbonization reaction, and thus affects the formation of carbon nanostructures during subsequent irradiation with a high-power ion beam. The possible mechanism of carbon nanostructures formation from chlorinated polyvinyl chloride under the impact of a high-power ion beam and the mechanism of the influence of preliminary heat treatment on it are considered. It has been established that different heat treatment temperatures lead to different morphologies of the resulting carbon nanostructures. On the control sample and the sample subjected to heating to 100 °C, only nanofibers are formed, preheating to 150 °C leads to the formation of a porous structure with nanosized pores under the nanofibers, and preheating to 200 °C leads to a significant decrease in the porosity and concentration of nanofibers.

Свойства мощного ионного пучка с энергией частиц до 1 МэВ, получаемого из плазмы, созданной высоковольтным импульсом на графитовом катоде

The features of the method for generating gas-vapor plasma and the characteristics of a high-power ion beam (HPIB) obtained in a vacuum diode with a graphite cathode using a plasma-forming high-voltage nanosecond pulse are described. The cathode material and the two-pulse mode of operation of the TEMP-4 type diode make it possible to form a multicomponent nanosecond HPIB with a maximum ion energy of up to 1 MeV, a particle flux density on the surface of ~ 1013 ion/cm2, and a power density on the sample surface of up to 107 W/cm2 to modify the surface properties of structural materials. Materials are published within the framework of scientific discussion. The authors invite researchers of the generation of high-power beams of non-gas ions and the processes of beam modification of solid-state materials to discuss the topics of this article.

Simulation and experimental studies on the formation of high-power titanium ion beams for the synergy of ion implantation and energy impact on the surface

The development of a material modification method based on synergy of high-intensity ion implantation and simultaneous energy impact on the surface is aimed at creating deep ion-doped layers. To implement this method, the high power density of pulsed and repetitively-pulsed beams of metal and gas ions with micro-submillisecond duration are required. The paper presents the results of numerical simulation and experimental studies on the formation of pulsed high-intensity metal ion beams from vacuum arc plasma. The ballistic focusing of heavy ions at injection currents from 0.1 to 1 A has been studied. The influence of the ion current density, accelerating voltage, and conditions for neutralizing the beam space charge on the transport and focusing of a high power density ion beam has been studied. The possibility of ballistic formation of submillisecond titanium ion beams with a pulse power density of a hundred kilowatts per square centimeter has been experimentally shown.

Formation of chemical compounds in the surface layers of titanium under the action of a high-power ion beam of nanosecond duration

The features of the change in the chemical state of the surface layers of commercially pure titanium under the action of a high-power ion beam (HPIB) were investigated using X-ray photoelectron spectroscopy (XPS). It has shown that HPIB irradiation leads to the interaction of titanium with carbon and nitrogen adsorbed on the surface and the formation of chemical compounds. The influence of the number of HPIB irradiation pulses on the formation of oxycarbonitride compounds in the surface layers of titanium has been established. Three possible mechanisms of the formation of titanium oxycarbonitride compounds during HPIB irradiation were considered: the interaction of molten titanium with adsorbed nitrogen and carbon-containing surface contaminants; the interaction of the evaporated titanium with the components of the residual atmosphere of the vacuum chamber, followed by the deposition of the resulting compounds on the surface and carbothermal reduction of the oxidized surface layer of titanium.

Исследование морфологии, химического состава и коррозионной стойкости твердого сплава «TiC–NiTi», модифицированного мощным ионным пучком

The article presents the results of a study of the effect of ion–beam treatment with a high–power ion beam (HPIB) on the change in topography, morphology, chemical composition and corrosion resistance of the surface layers of a tungsten–free hard alloy of the «TiC–NiTi» system. The samples are characterized by scanning electron microscopy, energy dispersive X–ray analysis, scanning probe microscopy, and metallographic analysis. It is revealed that due to the impact of HPIB, the surface layer of the sample undergoes melting with the formation of extended microcracks. At the same time, a decrease in the oxygen concentration from 24,6 to 13,7 at. % is recorded in the surface layer of the sample, and at some points on the sample it is completely absent. This result indicates the dissociation of titanium oxide under the influence of temperatures arising during HPIB irradiation. It is most likely that it is the thermal dissociation of titanium oxide and melting of the sample surface that are the main reasons for the increase in the corrosion resistance of the «TiC–NiTi» system alloy.

Численное моделирование динамики температурных полей в монокристаллическом кремнии при импульсно-периодической высокоинтенсивной ионной имплантации и энергетическом воздействии пучка на поверхность

Methods to modify surface and near-surface layers of materials and coatings by ion beams are used in many fields of science and technology. The method of high-intensity implantation by high-power density ion beams with submillisecond duration involves significant pulsed heating of the irradiated target’s near-surface layer, followed by its rapid cooling due to heat transfer into the material due to thermal conductivity and the implementation of repetitively-pulsed radiation-enhanced diffusion of atoms to depths exceeding the projective ion range. Using the numerical simulation, this work studies the dynamics of changes in temperature fields into silicon wafer under single-pulse and repetitively-pulsed exposure to submillisecond titanium ion beam with a pulsed power density in the range up to 109 W/m2. The conditions are determined under which the temperature in the ion-doped layer will correspond to the conditions of radiation-stimulated diffusion of the implanted element, and the temperature in the matrix material will not deteriorate its microstructure and properties.

Generation of high-power submillisecond metal ion beams

The possibility of using one grid electrode in the form of a part of a sphere for extraction from a free plasma boundary and focusing of metal ions is shown for the first time using titanium ions as an example to form a pulsed beam with a duration of 500 μs and a power density reaching 105 W/cm2. The results of studying the influence of the amplitude of the accelerating voltage in the range of 9-30 kV and the size of the grid cells on the efficiency of space charge neutralization and ion beam focusing are presented. Keywords: metal ions, vacuum arc plasma, submillisecond beams, high power density.