Effects Of Carbon Ion Implantation Research Articles

The effects of carbon ion implantation on wettability, abrasion, thermal and anti-corrosion stabilities of laser ablated super-hydrophobic Nitinol surface

Comparing with pure laser irradiation, the hybrid fabrication using laser ablation and chemical modification is one of the widely used techniques to obtain bio-inspired super-hydrophobic surface. Nevertheless, conventional surface chemical modification techniques have faced challenges including the detachment of micro-nano structures and the instability of super-hydrophobic surfaces. This research introduces an innovative method for creating extremely stable super-hydrophobic surfaces on NiTi alloy through a combination of laser exposure, carbon ion implantation, and modification with fluoroalkylsilane (FAS). Surface morphology and chemical component were systematically investigated to reveal the formation mechanism of super-hydrophobicity. Besides, its abrasion stability, thermal stability and corrosion resistance stability of this kind of super-hydrophobic surface were also investigated. And the corresponding stability improvement mechanisms were further revealed.

Effect of Carbon Ion Implantation and Xenon Ion Irradiation on the Tribological Properties of Titanium and Ti6Al4V Alloy

Effect of Carbon Ion Implantation and Xenon Ion Irradiation on the Tribological Properties of Titanium and Ti6Al4V Alloy

Adhesion Strength of Amorphous Carbon Films Deposited on a Trench Sidewall

Hydrogenated amorphous carbon (a-C:H) films were deposited on the sidewall of 3-mm-wide stainless steel or Si trench, and the adhesion strength of the films was evaluated using a micro-scratch tester. Particularly, the effects of carbon ion implantation and Si-containing interlayer (a-SiCx:H) as the pretreatments on the adhesion strength of the a-C:H films prepared on the trench sidewall were investigated. It was found that both carbon ion implantation and interlayer improved the adhesion strength of the a-C:H films deposited on the trench sidewalls. In addition, the carbon ion implantation dominated the adhesion strength of the a-C:H films for the Si substrates, and the interlayer for the stainless steel substrates. In the case of the stainless steel substrates, the carbon was accumulated on the surface of the trench sidewall instead of implantation, whereas the carbon ions were implanted to the Si substrates on the trench sidewall to form a mixing layer. The a-SiCx:H interlayer forms Fe–Si bonds between the stainless steel substrate and the interlayer, which is thought to improve the adhesion strength. It was also found that there is a negative correlation between the trench depth and the adhesion strength regardless of the pretreatment methods.

Carbon ion implantation as healing strategy for improved reliability in phase-change memory arrays

In this paper we investigate the effect of Carbon ion implantation in Ge2Sb2Te5 based Phase-Change Memory (PCM) targeting reliability improvement in 4 kb memory arrays. We show how ion implantation by beam line allows to localize the Carbon in a specific volume of the active layer, demonstrating that a low C concentration (lower than 5 at. %) can be achieved with a high control thanks to dose monitoring. We evidence an outstanding improvement of the PCM cell performances, in both single devices and 4 kb arrays, such as programming window widening and reduced variability of electrical parameters. We support our findings by TEM/EDS analyses demonstrating the healing effects of C ion implantation on interfaces and on retarding the phase-change layer segregation mechanisms.

Critical behavior and magnetocaloric effect in C-implanted Fe93Zr7 amorphous films

We report on the effect of carbon ion-implantation on the critical behavior of Fe93Zr7 amorphous films. Both the as-grown and carbon-implanted Fe93Zr7 samples exhibit a second order ferromagnetic to paramagnetic transition. The critical exponents were investigated through different techniques such as modified-Arrott plot, the critical isotherm analysis and the Windom scaling relation. Analysis of the critical behavior was presented in terms of the magnetocaloric effect around TC. While there is a significant increase of the magnetization and TC upon C-implantation, the critical exponents were only slightly affected by implantation and were in line with those of the 3D-Heisenberg model.

Effect of Carbon-Ion Implantation on the Surface Physical and Chemical Properties of Polylactic Acid, Hydroxyapatite and a Composite Based on Them

The results of investigation of the surface physical and chemical properties of polylactic acid, hydroxyapatite and a composite material based on them taken in the ratio of components 80/20, modified by carbon ions with exposure doses of 1 × 1015 and 1 × 1016 ion/cm2 at an accelerating voltage of 20 kV are presented. The surface chemical composition of the samples is studied by Fourier transform infrared spectroscopy. The elemental composition of the surface is studied by X-ray photoelectron spectroscopy. According to the obtained results, the simultaneous processes of destruction and cross linking of polylactic acid and polymer macromolecules are established. To assess the wettability of the untreated and modified surface of materials, contact-angle measurements and surface energy calculations are performed. It is established that carbon-ion implantation leads to improvement in the hydrophobic properties of materials; this process is accompanied by a decrease in the free surface energy.

Enhancement of superconducting parameters of MgB2 by low energy carbon ion implantation

The aim of work is to study the effects of carbon ion implantation on enhancement of superconducting properties of MgB2. Pure MgB2 bulk samples are irradiated by carbon ion beam of energy 40 keV (beam current 1 µA) at different fluences. After irradiation, there is enhancement in superconducting properties viz., critical current density (Jc), critical magnetic field (Hc2), comparing to pristine sample. Estimated with Ginzburg-Landau theory method at zero kelvin, the critical magnetic field Hc2(0) for irradiated sample shows an increase of 47 T than that of 38 T reported for pristine sample. There is also a four times increase in Jc after implantation. Improvement in grain connectivity with ion fluence is found in surface morphological studies. Raman spectroscopic studies show a shift in resonance peak related with E2g phonon modes after irradiation. This shifting is caused due to improvement in scattering and alteration of Fermi surface in implanted samples. These results are explained in correlation with the lattice disorder.

Effect of carbon ion implantation on the tribology of metal-on-metal bearings for artificial joints.

Metal-on-metal (MoM) bearings have become popular due to a major advantage over metal-on-polymer bearings for total hip arthroplasty in that the larger femoral head and hydrodynamic lubrication of the former reduce the rate of wear. However, concerns remain regarding adverse reactions to metal debris including metallosis caused by metal wear generated at the taper-head interface and another modular junction. Our group has hypothesized that carbon ion implantation (CII) may improve metal wear properties. The purpose of this study was to investigate the wear properties and friction coefficients of CII surfaces with an aim to ultimately apply these surfaces to MoM bearings in artificial joints. CII was applied to cobalt-chromium-molybdenum (Co-Cr-Mo) alloy substrates by plasma source ion implantation. The substrates were characterized using scanning electron microscopy and a 3D measuring laser microscope. Sliding contact tests were performed with a simple geometry pin-on-plate wear tester at a load of 2.5 N, a calculated contact pressure of 38.5 MPa (max: 57.8 MPa), a reciprocating velocity of 30 mm/s, a stroke length of 60 mm, and a reciprocating cycle count of 172,800 cycles. The surfaces of the CII substrates were generally featureless with a smooth surface topography at the same level as untreated Co-Cr-Mo alloy. Compared to the untreated Co-Cr-Mo alloy, the CII-treated bearings had lower friction coefficients, higher resistance to catastrophic damage, and prevented the adhesion of wear debris. The results of this study suggest that the CII surface stabilizes the wear status due to the low friction coefficient and low infiltration of partner materials, and these properties also prevent the adhesion of wear debris and inhibit excessive wear. Carbon is considered to be biologically inert; therefore, CII is anticipated to be applicable to the bearing surfaces of MoM prostheses.

Influence of 400 keV carbon ion implantation on structural, optical and electrical properties of PMMA

Ion implantation is a useful technique to modify surface properties of polymers without altering their bulk properties. The objective of this work is to explore the 400keV C+ ion implantation effects on PMMA at different fluences ranging from 5×1013 to 5×1015ions/cm2. The surface topographical examination of irradiated samples has been performed using Atomic Force Microscope (AFM). The structural and chemical modifications in implanted PMMA are examined by Raman and Fourier Infrared Spectroscopy (FTIR) respectively. The effects of carbon ion implantation on optical properties of PMMA are investigated by UV–Visible spectroscopy. The modifications in electrical conductivity have been measured using a four point probe technique. AFM images reveal a decrease in surface roughness of PMMA with an increase in ion fluence from 5×1014 to 5×1015ions/cm2. The existence of amorphization and sp2-carbon clusterization has been confirmed by Raman and FTIR spectroscopic analysis. The UV–Visible data shows a prominent red shift in absorption edge as a function of ion fluence. This shift displays a continuous reduction in optical band gap (from 3.13 to 0.66eV) due to formation of carbon clusters. Moreover, size of carbon clusters and photoconductivity are found to increase with increasing ion fluence. The ion-induced carbonaceous clusters are believed to be responsible for an increase in electrical conductivity of PMMA from (2.14±0.06)×10−10 (Ω-cm)−1 (pristine) to (0.32±0.01)×10−5 (Ω-cm)−1 (irradiated sample).

Effect of high-energy carbon ion implantation on Ti–Al–Si–N coatings by metal vapour vacuum arc

Due to the combination of high hardness, good thermal stability and oxidation resistance, Ti–Al–Si–N coatings have become an excellent candidate for use as high speed machining coatings. Nowadays ion implantation has been employed to alter the near-surface structure and properties of semiconductors, metals and metal alloys without the loss of bulk properties. The present research investigated the effect of carbon ion implantation on the structural, mechanical and tribological properties of the Ti–Al–Si–N coatings prepared by reactive unbalanced magnetron sputtering. Carbon implantation was carried out by metal vapour vacuum arc ion source (MEVVA) with different carbon ion doses. After implantation, the samples were investigated systematically by means of the Raman spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), cross-sectional transmission electron microscopy (TEM), X-ray photo-electron spectroscopy (XPS), surface profilometry (PGI), nano-indentation measurement and ball-on-disk test etc. The results showed that the implantation depth, chemical composition, microstructure and nanohardness depended strongly on the implanted carbon doses. In addition, a great improvement on the tribological performance was observed with the post-treatment process of carbon ion implantation.

Microstructural characterisation of carbon implanted austenitic stainless steel

Low carbon (316L) austenitic stainless steel has been implanted with carbon ions with a fluence of 5 × 10 17 C ions/cm 2 using an ion energy of 75 keV. The effect of carbon ion implantation on the microstructure of the austenitic steel has been examined in cross-section using transmission electron microscopy (TEM) both before and after implantation, and the implantation data correlated with a computer based simulation, TRIM (Transport and Range of Ions in Matter). It has been found that the high-fluence carbon ion implantation modified the microstructure of the steel, as demonstrated by the presence of two amorphous layers separated by a layer of expanded austenite.

Corrosion behavior of carbon-implanted zircaloy-4 in 1 M H 2SO 4

In order to study the effect of carbon ion implantation on the aqueous corrosion behavior, samples of zircaloy-4 were implanted with carbon ions with fluences ranging from 1 × 10 16 to 1 × 10 17 ions/cm 2, using a metal vapor vacuum arc source (MEVVA) operated at an extraction voltage of 40 kV. The valence states and depth distributions of elements in the surface layer of the samples were analyzed by X-ray photoelectron spectroscopy (XPS) and auger electron spectroscopy (AES), respectively. Glancing angle X-ray diffraction (GAXRD) was employed to examine the phase transformation due to the carbon ion implantation. The potentiodynamic polarization technique was employed to evaluate the aqueous corrosion resistance of implanted zircaloy-4 in a 1 M H 2SO 4 solution. It was found that a significant improvement was achieved in the aqueous corrosion behavior of zircaloy-4 implanted with carbon ions when the fluence is smaller than 5 × 10 16 ions/cm 2. The higher the fluence, the worse is the corrosion resistance. Finally, the mechanism of the corrosion behavior of carbon-implanted zircaloy-4 was discussed.

Corrosion behavior of carbon implanted ZIRLO alloy in 1 M H2SO4

In order to study the effect of carbon ion implantation on the aqueous corrosion behavior of ZIRLO alloy, specimens were implanted with carbon ions with fluence ranging from 1 x 10 16 to 1 × 10 17 ions/cm 2 , using a metal vapor vacuum arc source (MEVVA) at an extraction voltage of 40 kV. The valence states and depth distributions of elements in the surface layer of the samples were analyzed by X-ray photoelectron spectroscopy (XPS) and auger electron spectroscopy (AES), respectively. Transmission electron microscopy (TEM) was used to examine the microstructure of the carbon-implanted samples. Glancing angle X-ray diffraction (GAXRD) was employed to examine the phase transformation due to the carbon ion implantation. The potentiodynamic polarization technique was employed to evaluate the aqueous corrosion resistance of implanted ZIRLO alloy in a 1 M H 2 SO 4 solution. It was found that a significant improvement was achieved in the aqueous corrosion resistance of ZIRLO alloy implanted with carbon ions. The higher the fluence, the worse is the corrosion resistance. Finally, the mechanism of the corrosion behavior of carbon-implanted ZIRLO alloy was discussed.

Corrosion behavior of carbon-implanted M5 alloy in 1 M H 2SO 4

In order to study the effect of carbon ion implantation on the aqueous corrosion behavior of M5 alloy, specimens were implanted with carbon ions with fluence ranging from 1 × 10 16 to 1 × 10 17 ions/cm 2, using a metal vapor vacuum arc source (MEVVA) at an extraction voltage of 40 kV. The valence states and depth distributions of elements in the surface layer of the samples were analyzed by X-ray photoelectron spectroscopy (XPS) and auger electron spectroscopy (AES), respectively. Transmission electron microscopy (TEM) was used to examine the microstructure of the carbon-implanted samples. Glancing angle X-ray diffraction (GAXRD) was employed to examine the phase transformation due to the carbon ion implantation. The potentiodynamic polarization technique was employed to evaluate the aqueous corrosion resistance of implanted M5 alloy in a 1 M H 2SO 4 solution. It was found that a significant improvement was achieved in the aqueous corrosion resistance of M5 alloy implanted with carbon ions. The higher the fluence, the better is the corrosion resistance. Finally, the mechanism of the corrosion behavior of carbon-implanted M5 alloy was discussed.

A microstructural and mechanical study on the effects of carbon ion implantation on zirconia-toughened-alumina

Biomedical grade (>99.97% purity) alumina, zirconia and zirconia-toughened-alumina (ZTA) have been implanted with carbon ions at a dose of 5 × 1017 C ions/cm2 using an ion energy of 75 keV. The near-surface hardness of these bioceramics was examined using a load partial-unload indentation technique, both before and after implantation. The surfaces of the bioceramics have also been examined in cross-section using transmission electron microscopy (TEM) both before and after implantation and the implantation data correlated with a computer based simulation, TRIM (Transport and Range of Ions in Matter). The grinding and polishing treatment used prior to the implantation treatment has been found to have a strong influence on the surface microstructures for all three ceramics, although more significant modifications are brought about by carbon ion implantation. A comparison was made between the near-surface hardness of the unimplanted and carbon ion implanted surfaces of these bioceramics with relation to the modified microstructure. TEM examination of the implanted surfaces has demonstrated the formation of a sub-surface amorphous layer in all three materials as well as other microstructural modifications, such as microcracking and an increase in the near-surface dislocation density, that are characteristic of ion damage. The hardness data reveals that carbon ion implantation tends to decrease the surface hardness of alumina and zirconia with increasing ion dose, with a significant decrease occurring at the immediate near surface for both materials.

Effects of carbon ion pre-implantation on the mechanical properties of ta-C coatings on Ti-6Al-4V

We report on our investigations of the effects of carbon ion implantation into Ti-6Al-4V as a pre-treatment process prior to deposition of ta-C coatings using a filtered cathodic arc plasma method. A transition layer is formed that can be either TiC or TiC+C, providing an excellent interface for highly adherent ta-C coatings. We find that a smoothly-graded interface leads to good film–substrate adhesion, while ta-C films formed without a graded interface show poor adhesion. The film microhardness and wear performance are related to the implantation parameters via the thickness of the transition layer. Carbon ion implantation provides an effective pre-treatment method for ta-C coated Ti-6Al-4V substrate material.

Effect of carbon ion implantation on the structure and corrosion resistance of OT-4-0 titanium alloy

Abstract This work presents the results of investigation of the properties of OT-4-0 titanium alloy surface layers subjected to carbon implantation. Polished samples were implanted with carbon doses of 5×1015, 1×1016, 1×1017, and 2×1017 C+ cm−2 at an energy of 100 keV. The corrosion resistance was examined by the Stern and potentiodynamic methods in 0.9% NaCl solution at a temperature of 37°C. The composition and structure of the implanted layers were investigated by XPS, SIMS and TEM. The carbon implantation produced TiC precipitates at doses of 1×1016 C+ cm−2 or less, and a continuous solid layer of TiC at the further doses. The results from the electrochemical measurements provide evidence that carbon implantation at higher doses increases the corrosion resistance. The hardness of OT-4-0 titanium alloy is also improved.

Effects of ion implantation on Ti-6Al-4V on its frictional behaviour against UHMWPE

The aim of this work was to study the effect of carbon ion implantation and a DLC coating on the friction response of Ti-6Al-4V/UHMWPE materials used for biomedical implants, and on the endurance of the protective oxide layer of the Ti alloy at increasing loads. Carbon implantation was carried out at doses ranging from 2 × 10 17 to 10 × 10 17 ions cm −2 and energies from 75 to 180 keV. This implantation procedure produced a more than twofold improvement in hardness, as evaluated by a dynamic micro-indentation technique at increasing loads from 0.4 to 10 mN. Dry pin-on-disc tribological tests, using an UHMWPE pin, showed that some of the implantation treatments effectively protected the surface of the Ti alloy, without producing a break in the protective passive oxide layer and exhibited low friction values, similar to those obtained in DLC coatings. No direct correlation has been found, however, between the hardening induced by ion implantation and the improved tribological response. Formation of TiC precipitates could account for the hardening effect observed after carbon implantation and, in addition, implantation may cause stabilisation of the protective oxide layer on the titanium surface.

The effect of carbon ion implantation on the nucleation of diamond on Ti-6Al-4V alloy

The heterogeneous nucleation of diamond particles during the early stages of diamond film formation on non-diamond substrates is not well understood. In this work, we used ion implantation as a pretreatment process, to control the nucleation of diamond particles. The well known surgical alloy Ti-6Al-4V (“mirror” polished) was used as the substrate. Carbon ions at 30 keV energy were implanted at room temperature into masked regions on the samples, up to doses of 1×10 16-7×1 17 ions cm -2. At the high doses, carbon concentrations up to 80 at.% were generated as shown by Rutherford backscattering spectrometry (RBS). After ion implantation, diamond depositions were conducted at MRL utilizing a Toshiba microwave chemical vapour deposition (CVD) system. Operating conditions were 12 kPa total system pressure, 1% methane in hydrogen at a total flow of 100 standard cm 3 min -1, substrate temperature of 1000 °C, deposition time 5 h. The deposited films were studied by scanning electron microscopy, microfocus Raman scattering and RBS. The results indicate (a) a reduction in nucleation density up to 8 times with increasing ion dose, (b) near perfect diamond particles (Raman scattering) and (c) large internal stresses leading to partial flaking when the film becomes continuous. The role of a possible “carbided layer” formed by ion implantation is discussed.