Effect of surface modification by silicon ion beam on microstructure and chemical composition of near-surface layers of titanium nickelide

2013 ◽  
Vol 4 (5) ◽  
pp. 457-463 ◽  
Author(s):  
S. G. Psakh’e ◽  
A. I. Lotkov ◽  
S. N. Meisner ◽  
L. L. Meisner ◽  
V. P. Sergeev ◽  
...  
1994 ◽  
Vol 339 ◽  
Author(s):  
V. Heera ◽  
R. Kögler ◽  
W. Skorupa ◽  
J. Stoemenos

ABSTRACTThe evolution of the damage in the near surface region of single crystalline 6H-SiC generated by 200 keV Ge+ ion implantation at room temperature (RT) was investigated by Rutherford backscattering spectroscopy/chanelling (RBS/C). The threshold dose for amorphization was found to be about 3 · 1014 cm-2, Amorphous surface layers produced with Ge+ ion doses above the threshold were partly annealed by 300 keV Si+ ion beam induced epitaxial crystallization (IBIEC) at a relatively low temperature of 480°C For comparison, temperatures of at least 1450°C are necessary to recrystallize amorphous SiC layers without assisting ion irradiation. The structure and quality of both the amorphous and recrystallized layers were characterized by cross-section transmission electron microscopy (XTEM). Density changes of SiC due to amorphization were measured by step height measurements.


2020 ◽  
Vol 10 ◽  
pp. 5-18
Author(s):  
S. А. Ghyngаzоv ◽  
◽  
V. А. Коstеnко ◽  
A. K. Khassenov ◽  
◽  
...  

The article considers the influence of the treatment modes by N2+ and Ar+ ions beams on the physical and mechanical properties of zirconia ceramics. Surface modification of zirconia ceramics was performed using two modes of ion treatment — pulsed and continuous. The pulse mode of treatment by N2+ ions was realized at an accelerating voltage of 250 – 300 kV, current density j = 150 – 200 A/cm2, and energy density W = (3.5 and 5) ± 5 % J/cm2. The continuous mode of treatment by Ar+ ions was realized at an accelerating voltage of 30 kV and an ion current density of 300 and 500 μA/cm2. The fluence of the Ar+ ion beam varied from 1016 to 1018 cm–2. It is established that the pulsed mode of ion treatment leads to the melting and recrystallization of the surface of ceramics. It is shown that this treatment leads to a violation of the oxygen stoichiometry in ceramics and, as a result, there is an appearance of electrical conductivity in the near-surface layers, the layers of zirconia ceramics become conductive. It was established that the continuous mode of ion treatment does not lead to the melting and recrystallization of the ceramics surface, but is accompanied by its slight etching. It is shown that under the action of continuous ion treatment, microhardness increases (by 14 %). Hardening of the surface layers of ceramics is observed at a depth that exceeds the average projected range of Ar+ ion by 103 times.


2018 ◽  
Vol 781 ◽  
pp. 70-75
Author(s):  
Sergei Ghyngazov ◽  
Valeria Kostenko ◽  
Sergey Shevelev ◽  
Anatoliy I. Kupchishin ◽  
Aleksey Kondratyuk

The effect of ion irradiation on the strength characteristics of magnesium oxide and ceramics based on zirconia is studied. The MgO samples were a single crystal grown in an artificial manner. Samples of zirconium ceramics were prepared by ceramic technology. Irradiation of MgO crystals was carried out by Si+ ions (E = 150 keV), Fe+ (E = 70 keV), C+ (E = 50 keV) at room temperature. The fluence varied within the range (1016–1017) сm–2. The modification of the investigated types of ceramics was carried out by ions Al+ (Е = 60 keV), Ar+ (Е= 60 keV), N+ (E = 50 keV). We used ion beams of microsecond duration and moderate power (the current density in the pulse was 3 10-3 A/cm2). Fluence was 1017 cm-2. The irradiation of the ceramics with an ion beam C+ (E = 50 keV) was also performed with nanosecond duration (τ = 50 ns). It is established that ionic irradiation of magnesium oxide leads to an increase in crack resistance and a critical stress intensity factor. Irradiation of ceramics leads to hardening of its near-surface layers.


2017 ◽  
Author(s):  
A. I. Lotkov ◽  
A. L. Matveev ◽  
L. V. Artemyeva ◽  
S. N. Meysner ◽  
V. A. Matveeva ◽  
...  

1992 ◽  
Vol 7 (3) ◽  
pp. 717-724 ◽  
Author(s):  
J. Rankin ◽  
J.C. McCallum ◽  
L.A. Boatner

Time-resolved reflectivity and Rutherford backscattering spectroscopy were used to investigate the effects of regrowth environments on the thermally induced solid phase epitaxial (SPE) regrowth of amorphous near-surface layers produced by ion implantation of single-crystal SrTiO3. Water vapor in the regrowth atmosphere was found to alter both the apparent rate and activation energy of the SPE regrowth. For relatively dry atmospheres, a single constant regrowth rate is observed at any given temperature, and the activation energy is 1.2 ± 0.1 eV. When the concentration of H2O vapor in the atmosphere is increased, however, the regrowth activation energy effectively decreases to ∼0.95 eV. When regrown in atmospheres containing H2O vapor, the SrTiO3 amorphous layer exhibits two distinct stages of SPE regrowth as compared to the single rate found for dry anneals. This two-stage process apparently results from the diffusion of H/OH from the regrowth atmosphere at the surface of the crystal through the amorphous layer to the regrowing crystalline/amorphous interface.


2007 ◽  
Vol 363-365 ◽  
pp. 949-954 ◽  
Author(s):  
K. Sugiyama ◽  
T. Hayashi ◽  
K. Krieger ◽  
M. Mayer ◽  
K. Masaki ◽  
...  

2019 ◽  
Vol 813 ◽  
pp. 254-260
Author(s):  
Lucie Baudin ◽  
Monika Sitko ◽  
Cédric Garion ◽  
Paolo Chiggiato ◽  
Francesco Delloro ◽  
...  

Electron multipacting and electron cloud have been identified as being the major limiting factors for the beam quality or for the cryogenic system of high-intensity positive particles accelerators. Among conditioning operational techniques and other surface structuration techniques used to decrease the Secondary Electron Yield (SEY) of surfaces, laser surface treatment is a promising method to treat in situ and at atmospheric pressure copper surface of the vacuum chamber. Here, pulsed laser irradiation of copper in parallel lines pattern led to the local ablation and deposition of aggregates of copper particulates on the surface. Tests undertaken at CERN have shown that the modification of the surface morphology by creating roughness at different scales induces a decrease of the SEY by geometrical effects. Nevertheless, the mechanical strength and dust generation of the treated surface have not been addressed yet.In this work, a qualitative analysis of the multi-scale description of the surface morphology was carried out. Scanning Electron Microscopy (SEM), Focused Ion Beam (FIB), Transmission Electron Microscopy (TEM) and Energy Dispersive X-ray Spectroscopy (EDS) were used to investigate morphological characterization such as size and shape of the particulates, chemical composition, metallographic structures and phase transformation on the laser-processed surface.SEM and FIB examinations showed that the surface morphology depends on the local laser energy irradiating the surface and especially, relatively to the ablation threshold. TEM analysis revealed chemical composition and crystalline configuration of the treated material and helped to identify the laser modified and oxidized areas. A variety of superficial structures were observed. Potential vulnerable structures have been identified as oxidized matter redeposited on the ablated near surface. Material continuity and composition play a major role in the mechanical integrity of the generated surface morphology. The adherence of the created structures was assessed analyzing the origin of the dust extracted after mechanical stress.


2002 ◽  
Vol 158-159 ◽  
pp. 69-74
Author(s):  
A Föhl ◽  
H.D Carstanjen
Keyword(s):  
Ion Beam ◽  

2016 ◽  
Vol 7 (3) ◽  
pp. 325-329
Author(s):  
A. E. Ligachev ◽  
Yu. R. Kolobov ◽  
M. V. Zhidkov ◽  
E. V. Golosov ◽  
G. V. Potemkin ◽  
...  

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