Intense Ion-Beam Treatment of Materials

Abstract

Over the past decade, researchers in Japan, Russia, and the United States have been investigating the application of intense-pulsed-ion-beam (IPIB) technology (which has roots in inertial confinement fusion programs) to the surface treatment and coating of materials. The short range (0.1–10 μm) and high-energy density (1–50 J/cm2) of these short-pulsed (t ≥ 1 μs) beams (with ion currents I = 5–50 kA, and energies E = 100–1,000 keV) make them ideal flash-heat sources to rapidly vaporize or melt the near-surface layer of targets similar to the more familiar pulsed laser deposition (PLD) or laser surface treatment. The vaporized material can form coatings on substrates, and surface melting followed by rapid cooling (109 K/s) can form amorphous layers, dissolve precipitates, and form nonequilibrium microstructures.An advantage of this approach over laser processing is that these beams deliver 0.1–10 KJ per pulse to targets at expected overall electrical efficiencies (i.e., the ratio of extracted ion-beam energy to the total energy consumed in generating the beam) of 15–40% (compared to < 1% for the excimer lasers often used for similar applications). Consequently IPIB hardware can be compact and require relatively low capital investment. This opens the promise of environmentally conscious, low-cost, high-throughput manufacturing. Further, efficient beam transport to the target and excellent coupling of incident ion energy to targets are achieved, as opposed to lasers that may have limited coupling to reflective materials or produce reflecting plasmas at high incident fluence. The ion range is adjustable through selection of the ion species and kinetic energy, and the beam energy density can be tailored through control of the beam footprint at the target to melt (1–10 J/cm2) or to vaporize (10–50 J/cm2) the target surface. Beam pulse durations are short (≥ 1 μs) to minimize thermal conduction. Some disadvantages of IPIB processing over laser processing include the need to form and propagate the beams in vacuum, and the need for shielding of x-rays produced by relatively low-level electron current present in IPIB accelerators. Also these beams cannot be as tightly focused onto targets as lasers, making them unsuitable for applications requiring treatment on small spatial scales.

Influence of a high-power pulsed ion beam on the mechanical properties of corundum ceramics

“…The use of ceramics with gradient properties has great prospects, when the surface layer differs in its characteristics from the corresponding parameters of the bulk layers. As shown in works [11][12][13][14][15][16][17][18][19][20][21][22][23][24], surface treatment can be effectively carried out using low energy high current pulsed electron beam (LEHCPEB) [11][12][13], laser treatment [14,15] and high-power pulsed ion beam (HPPIB) [16][17][18][19][20][21][22][23][24]. To study thin modified layers of dielectrics, the method of secondary ion mass spectrometry [25][26][27] and the Rutherford backscattering method [28,29] have proved to be very useful.…”

“…They allow to carry out high-precision treatment of complex shaped ceramic parts with a short exposure time to the surface, are equipped with simple process automation, etc. Among radiation methods of influence on materials, the method of surface modification by highpower pulsed ion beams (HPPIB) [16][17][18][19][20][21][22][23][24] widely is used.…”

“…At present, studies are underway to modify the surface of metals and alloys by high-power pulsed ion beams [19][20][21][22]30]. At the same time, the physicochemical processes taking place in the nearsurface layers of dielectric materials under treatment HPPIB have been little studied.…”

The effect of powerful impulse charged particle beam parameters on intensity and energy efficiency of metal surface erosion

“…При этом способность МИП удалять вещество с об-лучаемой поверхности, т. е. вызывать ее эрозию, представляет большой интерес для исследовате-лей и создателей различных технологий обработ-ки материалов [1][2][3][4][5].…”

“…При этом способность МИП удалять вещество с об-лучаемой поверхности, т. е. вызывать ее эрозию, представляет большой интерес для исследовате-лей и создателей различных технологий обработ-ки материалов [1][2][3][4][5].Многочисленные экспериментальные иссле-дования показывают, что природа эрозии по-верхности под действием МИП ионов и электро-нов связана с сильным радиационным разогре-вом, вызываемым тормозящимися частицами, что приводит к испарению поверхности мише-ни [1][2][3]. Установлено, что интенсивность эро-зии, индикатором которой является коэффици-ент эрозии (т. е. количество атомов, удаленных с поверхности твердого тела, отнесенное к ко-личеству частиц пучка), на несколько порядков выше интенсивности столкновительного распы-ления поверхности твердого тела при непрерыв-ном облучении умеренными по плотности тока (J < 0,1 А/см 2 ) ионными пучками с аналогичны-ми значениями Е 0 [6][7][8][9].…”