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Yasuhiro Tanabe - One of the best experts on this subject based on the ideXlab platform.
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Graphitization behavior of the implanted Furan-Resin-derived carbon
Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, 2009Co-Authors: Yoshikazu Teranishi, Yasuhiro Tanabe, Tomohiro Kobayashi, Manabu Fukushima, Kazumasa Nakamura, Masanori Ishizuka, Atushi Mitsuo, Takahiko Uematsu, Nakamura Isao, Kenichi ShimizuAbstract:Abstract Ar or Xe ions were implanted into the fractured-faces or surfaces of as-carbonized glass-like carbon (GC) specimens for modification of the structure of them. Microstructural changes were examined by Raman spectroscopy, by scanning tunneling microscope (STM) and by transmission electron microscopy (TEM). It was found that the as-carbonized surfaces and fractured-faces of the specimens were changed to an amorphous structure by ion implantation. Implanted as-carbonized surfaces of specimens were restored nearly pristine structures after re-heat-treatment at 3000 °C. On the other hand, implanted fractured-faces of specimens resulted in well-developed structures after re-heat-treatment at 3000 °C. After re-heat-treatment at 3000 °C, the degree of graphitization on the implanted fractured-faces was higher than that on the pristine fractured-faces. It can be concluded that mobility of carbon atoms, or free face, seemed to play an important role on surface graphitization.
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Interior graphitization of Furan Resin-derived carbon by hot isostatic pressing
Materials Science and Engineering B-advanced Functional Solid-state Materials, 2007Co-Authors: Yoshikazu Teranishi, Eiichi Yasuda, Takashi Nishizawa, Tomohiro Kobayashi, Manabu Fukushima, Kazumasa Nakamura, Toru Maeda, Yasuhiro TanabeAbstract:Abstract This paper reports the investigation of morphological, textural and structural changes for Furan Resin-derived glass-like carbons, and the formation of spherical graphite in the carbon by hot isotropic pressing (HIP) at a temperature 2500 °C and under pressure 200 MPa even though the changed area took place at interior parts. We characterized the changed area by using Raman spectroscopy and XRD. It was found that the interior changes into graphite after HIP. From the scanning electron microscopy (SEM) images the interior part consisted of spheres, whose dimensions were about 20–150 μm. This graphitization is far from the previously reported ones on hard carbons even though the changed area was limited to interior.
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Radiation damages and bubble formation of ion implanted Furan-Resin-derived carbon
Surface and Coatings Technology, 2005Co-Authors: Yoshikazu Teranishi, Eiichi Yasuda, Tomohiro Kobayashi, Masaya Iwaki, Masato Kakihana, Manabu Fukushima, Kazumasa Nakamura, Yasuhiro TanabeAbstract:Abstract Furan-Resin-derived carbon generally produces a glass-like carbon (GC) having entangled graphene layers after high temperature heat treatments. However, Furan-Resin-derived carbon produced well-graphitized thin skin on surfaces after heat-treatment at 3000 °C. Since ion implantation is a useful technique for surface modification, we used them to investigate the mechanism of well-graphitized thin skin on surfaces of Furan-Resin-derived carbon after heat-treatment at 3000 °C. In this investigation, we observed morphological changes on Ar + or Xe + implanted GC surfaces using SEM&TEM and Raman spectroscopy. Ar or Xe ions were implanted into the Furan-Resin-derived carbon heat-treated at 3000 °C at energy of 60–160 keV at a fluence ranging from 1×10 15 to 1×10 17 ions/cm 2 . Microstructural changes were examined by Raman spectroscopy. The implanted surfaces of the specimens were changed to an amorphous structure by the ion implantation. Moreover, morphological SEM&TEM observations revealed that clear bubbles with diameter of 10–80 nm were present in the Ar + -implanted specimen at a fluence of 1×10 17 ions/cm 2 . However, bubbles did not appear in the Ar + -implanted specimen at a fluence of 1×10 16 ions/cm 2 . On the other hand, bubbles with diameter of 15–30 nm were present in the Xe + -implanted specimens at a fluence of 1×10 16 ions/cm 2 . The Xe + -implanted specimens were subjected to annealing of re-heat-treatment at 3000 °C. After the annealing, the bubbles were lost in the interior of specimens by cross-sectional SEM observations. Moreover, on the implanted surfaces appeared big bubbles, which were not presented on the implanted surface before annealing. The sizes of these big bubbles were about 2–10 μm. Using Raman spectroscopy, we observed that on the surface of the big bubbles the structure was re-well-graphitized. On the surface of non-bubbled areas it was less graphitized. Thus annealing provided a restoration of the structural, but much effective only on the bubble surfaces.
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TEM Observations of Surface Graphitization and Interior Microstructural Changes in a Furan-Resin-Derived Carbon
MRS Online Proceedings Library, 2003Co-Authors: Junji Yamanaka, Eiichi Yasuda, George C. Weatherly, Yasuhiro TanabeAbstract:Furan-Resin-derived carbon structures have attracted interest as a component in carbon based composite materials. We have investigated the microstructures of Furan-Resin-derived carbon by transmission electron microscopy after high-temperature heat treatments. We observed that graphitization occurred at the surface even although Furan-Resin-derived carbon is believed to be a non-graphitizable carbon. On the other hand the interior of the specimens exhibited a cage-like structure. Specimens heat-treated at higher temperatures exhibited a well-developed cage structure, as evidenced by the number of stacked layers and their periodicity. Post-column type EELS was utilized to study the chemical state of the interior of the specimens. All of the EELS spectra had a characteristic edge structure showing the existence of p bonding. There were not significant differences between the spectra of early-stage and well-developed cage structures.
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Oxidation behavior of Furan-Resin-derived carbon alloyed with Ta or Ti
Carbon, 2002Co-Authors: Yasuhiro Tanabe, Masao Utsunomiya, Manabu Ishibashi, Takashi Kyotani, Yutaka Kaburagi, Eiichi YasudaAbstract:Abstract The effect of Ti, Nb and Ta on the anti-oxidation of Furan-Resin-derived carbons was investigated by thermogravimetric analysis combined with gas/mass spectroscopy, Hall coefficient and magnetoresistance measurements, transmission electron microscopy, and X-ray diffraction analysis. Hall coefficient and magnetoresistance measurements revealed that the electronic properties of carbons with the above metal elements, and thus their crystallinity, are similar to that of neat carbon. The oxidation rates of the carbons with a small amount of Ti or Ta are decreased up to 1000 °C compared to that of neat carbon. The number of working active sites in carbons with Ta or Ti is smaller than that in carbons with Nb or neat carbon. Ta or Ti terminates some active sites in the carbons, or somehow modifies the structures of the active sites and retards the formation of oxygen–carbon intermediate products (surface complexes) on the materials. Thus, the oxidation rate of the carbons is decreased.
Eiichi Yasuda - One of the best experts on this subject based on the ideXlab platform.
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Interior graphitization of Furan Resin-derived carbon by hot isostatic pressing
Materials Science and Engineering B-advanced Functional Solid-state Materials, 2007Co-Authors: Yoshikazu Teranishi, Eiichi Yasuda, Takashi Nishizawa, Tomohiro Kobayashi, Manabu Fukushima, Kazumasa Nakamura, Toru Maeda, Yasuhiro TanabeAbstract:Abstract This paper reports the investigation of morphological, textural and structural changes for Furan Resin-derived glass-like carbons, and the formation of spherical graphite in the carbon by hot isotropic pressing (HIP) at a temperature 2500 °C and under pressure 200 MPa even though the changed area took place at interior parts. We characterized the changed area by using Raman spectroscopy and XRD. It was found that the interior changes into graphite after HIP. From the scanning electron microscopy (SEM) images the interior part consisted of spheres, whose dimensions were about 20–150 μm. This graphitization is far from the previously reported ones on hard carbons even though the changed area was limited to interior.
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Radiation damages and bubble formation of ion implanted Furan-Resin-derived carbon
Surface and Coatings Technology, 2005Co-Authors: Yoshikazu Teranishi, Eiichi Yasuda, Tomohiro Kobayashi, Masaya Iwaki, Masato Kakihana, Manabu Fukushima, Kazumasa Nakamura, Yasuhiro TanabeAbstract:Abstract Furan-Resin-derived carbon generally produces a glass-like carbon (GC) having entangled graphene layers after high temperature heat treatments. However, Furan-Resin-derived carbon produced well-graphitized thin skin on surfaces after heat-treatment at 3000 °C. Since ion implantation is a useful technique for surface modification, we used them to investigate the mechanism of well-graphitized thin skin on surfaces of Furan-Resin-derived carbon after heat-treatment at 3000 °C. In this investigation, we observed morphological changes on Ar + or Xe + implanted GC surfaces using SEM&TEM and Raman spectroscopy. Ar or Xe ions were implanted into the Furan-Resin-derived carbon heat-treated at 3000 °C at energy of 60–160 keV at a fluence ranging from 1×10 15 to 1×10 17 ions/cm 2 . Microstructural changes were examined by Raman spectroscopy. The implanted surfaces of the specimens were changed to an amorphous structure by the ion implantation. Moreover, morphological SEM&TEM observations revealed that clear bubbles with diameter of 10–80 nm were present in the Ar + -implanted specimen at a fluence of 1×10 17 ions/cm 2 . However, bubbles did not appear in the Ar + -implanted specimen at a fluence of 1×10 16 ions/cm 2 . On the other hand, bubbles with diameter of 15–30 nm were present in the Xe + -implanted specimens at a fluence of 1×10 16 ions/cm 2 . The Xe + -implanted specimens were subjected to annealing of re-heat-treatment at 3000 °C. After the annealing, the bubbles were lost in the interior of specimens by cross-sectional SEM observations. Moreover, on the implanted surfaces appeared big bubbles, which were not presented on the implanted surface before annealing. The sizes of these big bubbles were about 2–10 μm. Using Raman spectroscopy, we observed that on the surface of the big bubbles the structure was re-well-graphitized. On the surface of non-bubbled areas it was less graphitized. Thus annealing provided a restoration of the structural, but much effective only on the bubble surfaces.
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TEM Observations of Surface Graphitization and Interior Microstructural Changes in a Furan-Resin-Derived Carbon
MRS Online Proceedings Library, 2003Co-Authors: Junji Yamanaka, Eiichi Yasuda, George C. Weatherly, Yasuhiro TanabeAbstract:Furan-Resin-derived carbon structures have attracted interest as a component in carbon based composite materials. We have investigated the microstructures of Furan-Resin-derived carbon by transmission electron microscopy after high-temperature heat treatments. We observed that graphitization occurred at the surface even although Furan-Resin-derived carbon is believed to be a non-graphitizable carbon. On the other hand the interior of the specimens exhibited a cage-like structure. Specimens heat-treated at higher temperatures exhibited a well-developed cage structure, as evidenced by the number of stacked layers and their periodicity. Post-column type EELS was utilized to study the chemical state of the interior of the specimens. All of the EELS spectra had a characteristic edge structure showing the existence of p bonding. There were not significant differences between the spectra of early-stage and well-developed cage structures.
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Oxidation behavior of Furan-Resin-derived carbon alloyed with Ta or Ti
Carbon, 2002Co-Authors: Yasuhiro Tanabe, Masao Utsunomiya, Manabu Ishibashi, Takashi Kyotani, Yutaka Kaburagi, Eiichi YasudaAbstract:Abstract The effect of Ti, Nb and Ta on the anti-oxidation of Furan-Resin-derived carbons was investigated by thermogravimetric analysis combined with gas/mass spectroscopy, Hall coefficient and magnetoresistance measurements, transmission electron microscopy, and X-ray diffraction analysis. Hall coefficient and magnetoresistance measurements revealed that the electronic properties of carbons with the above metal elements, and thus their crystallinity, are similar to that of neat carbon. The oxidation rates of the carbons with a small amount of Ti or Ta are decreased up to 1000 °C compared to that of neat carbon. The number of working active sites in carbons with Ta or Ti is smaller than that in carbons with Nb or neat carbon. Ta or Ti terminates some active sites in the carbons, or somehow modifies the structures of the active sites and retards the formation of oxygen–carbon intermediate products (surface complexes) on the materials. Thus, the oxidation rate of the carbons is decreased.
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Cross-Sectional Observation of Surface Graphitization in Furan-Resin-Derived Carbon
MATERIALS TRANSACTIONS, 2001Co-Authors: Junji Yamanaka, Eiichi Yasuda, Hidekazu Migita, Yasuhiro TanabeAbstract:Carbons synthesized from thermosetting Resins are generally grouped into nongraphitizable carbons. Furan-Resin-derived carbon is one of the well-known nongraphitizable carbons. We investigated the microstructures of Furan-Resin-derived carbon by cross-sectional transmission electron microscopy, and found that graphitization occurred at the surface. This is the first cross-sectional observation of surface graphitization in Furan-Resin-derived carbon. The surface graphite layer was approximately 20 or 30 nm in thickness in the specimen heat-treated at 3273 K for 1800 s. Atomic stacking in the layer was parallel to the specimen surface. The interior of the specimen was not graphitic but a cage structure.
Liliana Beatriz Manfredi - One of the best experts on this subject based on the ideXlab platform.
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development of low environmental impact protective coatings based on a Furan Resin and cellulose nanocrystals
Progress in Organic Coatings, 2019Co-Authors: L Asaro, I T Seoane, L A Fasce, Viviana P Cyras, Liliana Beatriz ManfrediAbstract:Abstract A Furan Resin, synthesized from furfural and phenol, was previously proposed as a less environmental impact alternative to traditional phenolics’ coatings to protect aluminum. In this work, the Furan Resin was modified with 10 and 20%wt of prepared cellulose nanocrystals (CNC), a biobased nanoreinforcement. Several techniques such as AFM, FTIR, DMA, TGA, XRD, nanoindentation experiments and contact angle measurements were applied to characterize CNC, coatings mechanical performance, materials thermal degradation behavior and chemical structure. It was found that all materials show an excellent interfacial adhesion with the aluminum substrate. CNC incorporation enhances coatings’ mechanical resistance to permanent damage and unexpectedly reduces the elastic modulus. This is because CNC affects the polymerization hindering Furan matrix crosslinking. CNC addition slightly accelerates the thermal degradation rate in the overall degradation zone of Furan Resin keeping the same degradation mechanism and the formation of the protective char.
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Furan Resins as replacement of phenolic protective coatings structural mechanical and functional characterization
Progress in Organic Coatings, 2014Co-Authors: Guadalupe Rivero, Laura Alejandra Fasce, Silvia Cere, Liliana Beatriz ManfrediAbstract:Abstract Phenolic coatings are usually a convenient and economical way to protect metallic materials against wear and corrosion. Furan Resins are analogous to phenolics, as they are obtained by replacing formaldehyde by furfural in their formulation. In this work, a Furan Resin based on furfural and phenol was synthesized and used as an aluminum coating. Thus, toxic emissions of formaldehyde were avoided, while a biobased derivative was used instead. The performance of the proposed Resin was compared with the one of a traditional phenolic Resin. Physicochemical characteristics including chemical structure, surface polarity and glass transition temperature were evaluated by means of Fourier transform infrared spectroscopy, contact angle measurements and dynamic–mechanical analysis, respectively. Nanomechanical and nanotribological properties were assessed by depth sensing indentation techniques. As well, the corrosion resistance of the Furan coating was determined by potentiodynamic polarization tests. The obtained results validate the Furan Resin as a feasible alternative to phenolics to protect aluminum.
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Furan Resin as a replacement of phenolics: influence of the clay addition on its thermal degradation and fire behaviour
Fire and Materials, 2013Co-Authors: Guadalupe Rivero, Sara Villanueva, Liliana Beatriz ManfrediAbstract:Summary Nanocomposites based on a Furan Resin and different types of clays were obtained. Their thermal and fire behaviours were compared with traditional phenolic Resins, which are known by their excellent flame resistance. Three types of montmorillonite clays were in situ added to the thermosetting matrix. A cone calorimeter and a smoke chamber were used to evaluate the performance of the materials against fire and their smokes generation. Global parameters were calculated for comparison purposes. Fires derived from the Furan Resin combustion grow faster than the phenolic ones, but they are extinguished more rapidly. This effect is enhanced by the incorporation of inorganic nanofillers. The only addition of any clay causes shorter fires but slightly speeds up the degradation process. A homogeneous nanofiller dispersion was found to be crucial to achieve good fire behaviour. Nevertheless, for materials with similar dispersion, the crosslinking degree of the polymer matrix appears as a secondary factor that determines slighter differences in the performance. Nanocomposites with organomodified clays showed a quite similar fire performance, though the composite containing the clay (Southern Clay Products, Inc., Louisville, Ky, USA) Cloisite®30B showed the best performance taking into account both the fire risk and the smoke evolution and obscuration. Copyright © 2013 John Wiley & Sons, Ltd.
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Curing kinetics of a Furan Resin and its nanocomposites
Thermochimica Acta, 2011Co-Authors: Guadalupe Rivero, Valeria Pettarin, Analía Vázquez, Liliana Beatriz ManfrediAbstract:Abstract A Furan Resin was synthesized from furfural and phenol and it was expected to have similar properties to the commonly used phenolic Resins because the former was obtained by the replacement of formaldehyde by furfural, reducing the dangerous formaldehyde emissions. In the present work, nanocomposites were obtained by the in situ addition of 2% of different types of clays to the Furan Resin to enhance the polymer performance. Montmorillonite natural clay Cloisite® Na+ and the chemically modified ones, Cloisite® 30B and Cloisite® 10A were used. A clay dispersion comparison among the nanocomposites was performed. The curing kinetics of the Furan Resin and its composites was characterized by Differential Scanning Calorimetry. Free kinetic models were applied in order to obtain and compare the activation energy of each process. Vyazovkin numerical analysis was found to provide the most accurate method to analyze the variation of the activation energy (E) with the reaction conversion. Some differences arise in the activation energy vs. conversion profile among the materials studied. These differences were related to the variations in the viscosity and the chemical groups with the evolution of the curing reaction, followed by infrared spectroscopy. The nanocomposites containing the organically modified clays showed an additional peak in the last stage of the curing process due to parallel reactions including the beginning of the organic modifier decomposition.
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Synthesis and characterization of nanocomposites based on a Furan Resin
Journal of Applied Polymer Science, 2010Co-Authors: Guadalupe Rivero, Analía Vázquez, Liliana Beatriz ManfrediAbstract:Formaldehyde emissions are nowadays trying to be reduced because of its atmospheric pollutant character. Besides, it is encouraged the use of polymeric materials synthesized from biomass wastes as row materials. For this reason, Furan Resins would be an alternative to phenolic Resins, where formaldehyde is replaced by furfural as a reactant. Regarding, the addition of nanoparticles to the Furan Resin should enhance their performance as metal coatings with good thermal and oxidative resistance. The aim of this article is to study the influence of the in situ addition of different type of nanoparticles on the chemical reactions involved in the synthesis of a Furan Resin. From the viscosity measurements it was observed that the addition of the nanoreinforcements led to a higher Resin reaction rate. Differences in the final chemical structure among the materials were also observed by infrared spectroscopy analyses. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Giovanni Camino - One of the best experts on this subject based on the ideXlab platform.
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thermal and combustion behavior of Furan Resin silica nanocomposites
European Polymer Journal, 2015Co-Authors: Marco Monti, Hans Hoydonckx, Frank Stappers, Giovanni CaminoAbstract:In this paper, we report the development of Furan Resin nanocomposites, filled with silica nanoparticles. In order to have a dispersion procedure, which could be easily up-scalable to the industrial level, a commercially available water-based suspension of silica particles was used. This was possible thanks to the fact that water is a good solvent of Furan Resin. Different treatments with silanes were performed in order to improve the interaction between the silica particles and the Furan matrix. As a result, the thermal oxidative resistance of the Furan Resin is improved with also a minor improvement of fire reaction, which is already quite substantial in the pristine Resin.
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Thermal and combustion behavior of Furan Resin/silica nanocomposites
European Polymer Journal, 2015Co-Authors: Marco Monti, Hans Hoydonckx, Frank Stappers, Giovanni CaminoAbstract:In this paper, we report the development of Furan Resin nanocomposites, filled with silica nanoparticles. In order to have a dispersion procedure, which could be easily up-scalable to the industrial level, a commercially available water-based suspension of silica particles was used. This was possible thanks to the fact that water is a good solvent of Furan Resin. Different treatments with silanes were performed in order to improve the interaction between the silica particles and the Furan matrix. As a result, the thermal oxidative resistance of the Furan Resin is improved with also a minor improvement of fire reaction, which is already quite substantial in the pristine Resin.
Kazumasa Nakamura - One of the best experts on this subject based on the ideXlab platform.
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Magnetic properties of magnetic glass-like carbon prepared from Furan Resin alloyed with magnetic fluid
Journal of Magnetism and Magnetic Materials, 2017Co-Authors: Kazumasa Nakamura, Kyoko Okuyama, Tsugiko TakaseAbstract:Abstract Magnetic glass-like carbons that were heat-treated at different temperatures or were filled with different magnetic nanoparticle contents were prepared from Furan Resin alloyed with magnetic fluid (MF) or Fe3O4 powder in their liquid-phase states during mixing. Compared to the Fe3O4 powder-alloyed carbon, the MF-alloyed carbon has highly dispersed the nanoparticles, and has the excellent saturation magnetization and coercivity. It is implied that saturation magnetizations are related to changes in the types of phases for the nanoparticles and the relative intensities of X-ray diffraction peaks for iron and iron-containing compounds in the carbons. Additionally, the coercivities are possibly affected by the size and crystallinity of the nanoparticles, the relative amounts of iron, and the existence of amorphous compounds on the carbon surfaces.
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Graphitization behavior of the implanted Furan-Resin-derived carbon
Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, 2009Co-Authors: Yoshikazu Teranishi, Yasuhiro Tanabe, Tomohiro Kobayashi, Manabu Fukushima, Kazumasa Nakamura, Masanori Ishizuka, Atushi Mitsuo, Takahiko Uematsu, Nakamura Isao, Kenichi ShimizuAbstract:Abstract Ar or Xe ions were implanted into the fractured-faces or surfaces of as-carbonized glass-like carbon (GC) specimens for modification of the structure of them. Microstructural changes were examined by Raman spectroscopy, by scanning tunneling microscope (STM) and by transmission electron microscopy (TEM). It was found that the as-carbonized surfaces and fractured-faces of the specimens were changed to an amorphous structure by ion implantation. Implanted as-carbonized surfaces of specimens were restored nearly pristine structures after re-heat-treatment at 3000 °C. On the other hand, implanted fractured-faces of specimens resulted in well-developed structures after re-heat-treatment at 3000 °C. After re-heat-treatment at 3000 °C, the degree of graphitization on the implanted fractured-faces was higher than that on the pristine fractured-faces. It can be concluded that mobility of carbon atoms, or free face, seemed to play an important role on surface graphitization.
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Interior graphitization of Furan Resin-derived carbon by hot isostatic pressing
Materials Science and Engineering B-advanced Functional Solid-state Materials, 2007Co-Authors: Yoshikazu Teranishi, Eiichi Yasuda, Takashi Nishizawa, Tomohiro Kobayashi, Manabu Fukushima, Kazumasa Nakamura, Toru Maeda, Yasuhiro TanabeAbstract:Abstract This paper reports the investigation of morphological, textural and structural changes for Furan Resin-derived glass-like carbons, and the formation of spherical graphite in the carbon by hot isotropic pressing (HIP) at a temperature 2500 °C and under pressure 200 MPa even though the changed area took place at interior parts. We characterized the changed area by using Raman spectroscopy and XRD. It was found that the interior changes into graphite after HIP. From the scanning electron microscopy (SEM) images the interior part consisted of spheres, whose dimensions were about 20–150 μm. This graphitization is far from the previously reported ones on hard carbons even though the changed area was limited to interior.
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Radiation damages and bubble formation of ion implanted Furan-Resin-derived carbon
Surface and Coatings Technology, 2005Co-Authors: Yoshikazu Teranishi, Eiichi Yasuda, Tomohiro Kobayashi, Masaya Iwaki, Masato Kakihana, Manabu Fukushima, Kazumasa Nakamura, Yasuhiro TanabeAbstract:Abstract Furan-Resin-derived carbon generally produces a glass-like carbon (GC) having entangled graphene layers after high temperature heat treatments. However, Furan-Resin-derived carbon produced well-graphitized thin skin on surfaces after heat-treatment at 3000 °C. Since ion implantation is a useful technique for surface modification, we used them to investigate the mechanism of well-graphitized thin skin on surfaces of Furan-Resin-derived carbon after heat-treatment at 3000 °C. In this investigation, we observed morphological changes on Ar + or Xe + implanted GC surfaces using SEM&TEM and Raman spectroscopy. Ar or Xe ions were implanted into the Furan-Resin-derived carbon heat-treated at 3000 °C at energy of 60–160 keV at a fluence ranging from 1×10 15 to 1×10 17 ions/cm 2 . Microstructural changes were examined by Raman spectroscopy. The implanted surfaces of the specimens were changed to an amorphous structure by the ion implantation. Moreover, morphological SEM&TEM observations revealed that clear bubbles with diameter of 10–80 nm were present in the Ar + -implanted specimen at a fluence of 1×10 17 ions/cm 2 . However, bubbles did not appear in the Ar + -implanted specimen at a fluence of 1×10 16 ions/cm 2 . On the other hand, bubbles with diameter of 15–30 nm were present in the Xe + -implanted specimens at a fluence of 1×10 16 ions/cm 2 . The Xe + -implanted specimens were subjected to annealing of re-heat-treatment at 3000 °C. After the annealing, the bubbles were lost in the interior of specimens by cross-sectional SEM observations. Moreover, on the implanted surfaces appeared big bubbles, which were not presented on the implanted surface before annealing. The sizes of these big bubbles were about 2–10 μm. Using Raman spectroscopy, we observed that on the surface of the big bubbles the structure was re-well-graphitized. On the surface of non-bubbled areas it was less graphitized. Thus annealing provided a restoration of the structural, but much effective only on the bubble surfaces.
