Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Kurata, Yuji; Sato, Hidetomo*; Yokota, Hitoshi*; Suzuki, Tetsuya*
Proceedings of 2nd International Workshop on Structural Materials for Innovative Nuclear Systems (SMINS-2), p.177 - 188, 2012/12
Liquid lead-bismuth is a candidate material used for innovative nuclear systems such as accelerator driven reactors and fast reactors. Development of corrosion resistant materials in liquid lead-bismuth is one of important research subjects to realize these systems. In this study, improvement of corrosion properties in lead-bismuth by Al alloy coating was investigated. Aluminum alloys were coated on 316SS using sheets made of Al, Ti and Fe powders, and laser heating. Adjustments of chemical composition in sheets and scanning rate of laser beam enabled us to control Al concentration in coating layers. The corrosion tests were conducted at 550
C for 1,000 hours or 3,000 hours in oxygen-controlled lead-bismuth. As a result of the corrosion tests, it was found that the coating with Al concentration of 5 to 8 mass% showed good corrosion resistance.
Kurata, Yuji; Yokota, Hitoshi*; Suzuki, Tetsuya*
Journal of Engineering for Gas Turbines and Power, 134(6), p.062902_1 - 062902_7, 2012/06
Times Cited Count：10 Percentile：42.93(Engineering, Mechanical)Nuclear systems using lead alloys are one of the promising reactor concepts with improved safety. This paper focuses on development of Al-alloy coating for nuclear systems using liquid lead-bismuth eutectic (LBE). It is necessary to improve corrosion resistance of steels because of high corrosiveness of liquid LBE at high temperatures. An Al-alloy coating method using Al, Ti and Fe powders and laser beam heating has been developed. Main defects formed in an Al-powder-alloy coating process are surface defects and cracks. Conditions required to avoid these defects have been studied. According to results of the corrosion tests at 550C in liquid LBE, the Al-alloy coating layers on 316SS prevent severe corrosion attack observed in 316SS without coating. The good corrosion resistance of the Al-alloy coating is based on the thin Al-oxide film regenerated in liquid LBE. It is estimated that the range of the adequate Al concentration in the coating layer is from 4 to 12 wt%.
Kurata, Yuji; Yokota, Hitoshi*; Suzuki, Tetsuya*
Journal of Nuclear Materials, 424(1-3), p.237 - 246, 2012/05
Times Cited Count：32 Percentile：88.87(Materials Science, Multidisciplinary)An Al-alloy coating method using Al, Ti and Fe powders and the laser beam heating has been developed for nuclear systems using liquid lead-bismuth eutectic (LBE). The main defects formed in the Al-alloy coating process are surface defects and cracks. Conditions required to avoid such defects have been studied. A static corrosion test was conducted in liquid LBE at the controlled oxygen concentrations of 10
to 10
wt% at 550C for 3000h. The Al-alloy coating layer on 316SS prevents severe corrosion attack such as Ni dissolution, partial loss of grains and LBE penetration observed in the 316SS without Al-alloy coating. The Al-alloy coating layer, which is formed without surface defects and cracks under the optimum condition, exhibits good corrosion resistance in liquid LBE.
Kurata, Yuji; Yokota, Hitoshi*; Suzuki, Tetsuya*
Proceedings of ASME 2011 Small Modular Reactors Symposium (SMR 2011) (CD-ROM), 7 Pages, 2011/09
Small and medium reactors using lead alloys as coolant are one of the promising reactor concepts with improved safety. This paper focuses on development of Al-alloy coating for nuclear systems using liquid lead-bismuth eutectic (LBE). Since corrosion attack becomes severe against steels at high temperatures, it is necessary to improve corrosion resistance. An Al-alloy coating method using Al, Ti and Fe powders, and laser beam heating has been developed. Main defects formed in an Al-powder-alloy coating process are surface defects and cracks. Conditions required to avoid these defects were found. According to results of the corrosion tests at 550 C in liquid LBE, the Al-alloy coating layers on 316SS protect severe corrosion attack observed in 316SS without coating. From the viewpoints of the soundness of coating layers and preservation of their corrosion resistance, it is estimated that the range of the adequate Al concentration in the coating layer is from 4 to 12 wt%.
Kurata, Yuji; Sato, Hidetomo*; Yokota, Hitoshi*; Suzuki, Tetsuya*
Materials Transactions, 52(5), p.1033 - 1040, 2011/05
Times Cited Count：13 Percentile：54.96(Materials Science, Multidisciplinary)A new Al-alloy coating method using Al, Ti and Fe powders has been applied to 316SS in order to develop corrosion resistant coating in lead-bismuth eutectic (LBE). The 316SS plates with coating layers of different Al concentrations were tested at 550C for 1000h in liquid LBE with controlled oxygen concentrations of 10
10
mass%. While surface oxidation and grain boundary corrosion accompanied by LBE penetration are observed in 316SS without Al-alloy coating, the Al-alloy coating is effective to protect such severe corrosion attacks in LBE. Although the coating layer containing 2.8 mass% Al does not always keep sufficient corrosion resistance, good corrosion resistance is obtained in the coating layer where the average Al concentration is 4.2 mass%. Cracks are found in the coating layer containing 17.8 mass% Al. The Al-powder-alloy coating applied to 316SS is promising as a corrosion resistant coating method in liquid LBE environment.
cv. Acapulco.Kondo, Masayoshi*; Koike, Yosuke*; Hase, Yoshihiro; Yokota, Yuichiro; Kobayashi, Hitoshi*
JAEA-Review 2007-060, JAEA Takasaki Annual Report 2006, P. 75, 2008/03
no abstracts in English
-rays; Guineagrass and sorghumNakagawa, Hitoshi*; Inafuku, Masashi*; Kusaba, Makoto*; Yamaguchi, Hiroyasu*; Morishita, Toshikazu*; Morita, Ryohei*; Nishimura, Minoru*; Hoeman, S.*; Yokota, Yuichiro; Hase, Yoshihiro; et al.
JAEA-Review 2007-060, JAEA Takasaki Annual Report 2006, P. 72, 2008/03
no abstracts in English
rayMorita, Ryohei*; Morishita, Toshikazu*; Nakagawa, Hitoshi*; Nishimura, Minoru*; Yamaguchi, Hiroyasu*; Yokota, Yuichiro; Hase, Yoshihiro; Tanaka, Atsushi
JAEA-Review 2006-042, JAEA Takasaki Annual Report 2005, P. 78, 2007/02
no abstracts in English
hort (
)Kondo, Masayoshi*; Ogata, Keiji*; Hase, Yoshihiro; Yokota, Yuichiro; Narumi, Issei; Kobayashi, Hitoshi*
JAEA-Review 2006-042, JAEA Takasaki Annual Report 2005, P. 89, 2007/02
no abstracts in English
raysMorita, Ryohei*; Morishita, Toshikazu*; Nakagawa, Hitoshi*; Nishimura, Minoru*; Yamaguchi, Hiroyasu*; Yokota, Yuichiro; Hase, Yoshihiro; Tanaka, Atsushi
no journal, ,
no abstracts in English
plantKondo, Masayoshi*; Ogata, Keiji*; Kobayashi, Hitoshi*; Hase, Yoshihiro; Yokota, Yuichiro
no journal, ,
no abstracts in English
Kurata, Yuji; Sato, Hidetomo*; Yokota, Hitoshi*; Suzuki, Tetsuya*
no journal, ,
Liquid lead-bismuth is a candidate material used for accelerator driven systems and fast reactors. Development of corrosion resistant materials in liquid lead-bismuth is one of important research subjects to realize these systems. In this study, effect of Al concentration in coating layer on corrosion properties in lead-bismuth was investigated for the purpose of improvement of corrosion properties of 316SS by an Al powder alloy coating method. Aluminum alloys were coated on 316SS using sheets made of Al, Ti and Fe powders, and laser heating. The corrosion test was conducted at 550C for 3000h in liquid lead-bismuth. The coating with about 2 mass% of Al did not exhibit enough corrosion resistance. Cracks were found in the coating with 13 to 15 mass% of Al. The coating with about 8 mass% of Al showed good corrosion resistance without cracking.
ray; Guinea grass and sorghumNakagawa, Hitoshi*; Inafuku, Masashi*; Kusaba, Makoto*; Yamaguchi, Hiroyasu*; Morishita, Toshikazu*; Morita, Ryohei*; Nishimura, Minoru*; Hoeman, S.*; Yokota, Yuichiro; Hase, Yoshihiro; et al.
no journal, ,
no abstracts in English
Kondo, Masayoshi*; Koike, Yosuke*; Kobayashi, Hitoshi*; Hase, Yoshihiro; Yokota, Yuichiro
no journal, ,
no abstracts in English
Kondo, Masayoshi*; Koike, Yosuke*; Okudera, Yosuke*; Miyajima, Toshinari*; Nomizu, Toshikazu*; Hase, Yoshihiro; Yokota, Yuichiro; Kobayashi, Hitoshi*
no journal, ,
no abstracts in English
Kurata, Yuji; Sato, Hidetomo*; Yokota, Hitoshi*; Suzuki, Tetsuya*
no journal, ,
Liquid lead-bismuth is a candidate material used for accelerator driven systems and fast reactors. Development of corrosion resistant materials in liquid lead-bismuth is one of important research subjects to realize these systems. In this study improvement of corrosion resistance of 316SS was investigated by means of aluminum powder alloy coating. Aluminum alloys were coated on 316SS using sheets made of Al, Ti and Fe powders, and laser heating. The corrosion test was conducted at 550C for 1000h in liquid lead-bismuth where oxygen concentrations were controlled to be about 510mass%. As a result of the corrosion test, it was found that Al alloy coating protected grain boundary corrosion and surface oxidation of Fe and Cr, which were significant in 316SS substrate.
Yokota, Hitoshi*; Sato, Hidetomo*; Suzuki, Tetsuya*; Maekawa, Katsuhiro*; Kurata, Yuji
no journal, ,
Liquid lead-bismuth is a candidate material of a spallation target and a coolant of accelerator driven systems for transmutation of high-level radioactive wastes. Compatibility of steels and lead-bismuth is one of critical issues. In order to solve the problem, Al powder alloy coating on 316SS was investigated. The Al alloy coating was conducted by scanning a YAG laser beam on Al-Ti-Fe sheets under Ar gas environment. Coating parameters are chemical compositions of sheet material, scanning rates of laser beam etc. Cracks often formed in the coating layer when Al contents in sheet material were high. From detail analyses, knowledge of crack formation was obtained in Al powder alloy coating using this method.
Kurata, Yuji; Sato, Hidetomo*; Yokota, Hitoshi*; Suzuki, Tetsuya*
no journal, ,
Liquid lead-bismuth is a candidate material used for accelerator driven systems and fast reactors. Development of corrosion resistant materials in liquid lead-bismuth is one of important research subjects to realize these systems. In this study, improvement of corrosion properties in lead-bismuth by Al alloy coating was investigated. Aluminum alloys were coated on 316SS using sheets made of Al, Ti and Fe powders, and laser heating. Adjustments of chemical composition in sheets and scanning rate of laser beam enabled us to control Al concentration in coating layers. The corrosion test was conducted at 550C for 3000h in oxygen-controlled lead-bismuth. As a result of the corrosion test, it was found that the coating with Al concentration of 5 to 8 mass% showed good corrosion resistance.
Yokota, Hitoshi*; Suzuki, Tetsuya*; Kurata, Yuji
no journal, ,
Liquid lead-bismuth eutectic (LBE) is used as a material of high power spallation targets and coolant of accelerator driven systems for transmutation of long-lived radioactive wastes. Since corrosion attack becomes severe against structural steels at high temperatures in liquid LBE, it is necessary to improve corrosion resistance of steels. An Al-alloy coating method using Al, Ti and Fe powders, and laser beam heating has been developed. Main defects formed in the Al-powder-alloy coating process are surface defects and cracks. Laser beam scanning rates and Al concentration in the coating layer were adjusted to avoid these defects. According to results of the corrosion test at 550C for 3000h, liquid LBE penetrates into surface defects while it is hard to penetrate into cracks in the coating layer. It is found that the Al-alloy coating layers on 316SS protect severe corrosion attack such as grain boundary corrosion and LBE penetration observed in 316SS without coating.
powder) in mechanical treatment cell at Tokai Reprocessing PlantFuruuchi, Yuta; Sato, Shinji; Yatabe, Hitoshi; Yokota, Satoru; Yamada, Takashi; Yahagi, Fumio; Terunuma, Hirotaka; Tokoro, Takeshi; Takahashi, Akihiro; Iijima, Shizuka; et al.
no journal, ,
Clean-up activity of spent fuel powder (UO powder) in mechanical treatment cell was performed for the purpose of the preparation of decommissioning at TRP. For the clean-up activity, we selected an inexpensive vacuum cleaner and made tools, that was improved taking into account of use by means of a crane or a manipulator in the high dose cell, and applied it after a mock-up test. We report our experience and knowledge provided through this clean-up activity.
