K. Tsuchiya

M. Ito

M. Matsuyama

S. Kitagishi

T. Nagasaka

Y. Hanawa

Y. Hatano

Y. Hishinuma

National Institute for Fusion Science (NIFS-Repository)

In conclusion, the surface change of each Be samplewas observed by the corrosion test and influenced by thecontent of BeO and the grain size of the beryllium grades.In future, the corrosion mechanism of beryllium sampleswill be investigated from the results ofXPS measurement.Table 1 Properties of beryllium samples1500 ,----------------,1) Tsuchiya, K.: Annual Report ofNIFS, (2011) p.545.10010Be sMaterial Bery Ilium MetalGrade &200F &65H j-220H=tlape (mm) f10x1.5 f 10x1.5 flOx1.5Density (g/cm3) 1.855 1.848 1.861Grain size (fJITl) 10,3 6,9 5,6Element (%)Be 99,00 99.40 98,60BeQ 1.00 0,70 1.90QAI 0,05 0,04 0,01Fe 0,12 0,08 0,06Si 0.D3 0,02 0,02,-,..i llXD::? 500:;;2 4 6 8EI apsed Time (x lOJtl)Fig. 1. Change of electric conductivity of each Be sampleduring corrosion test.?? 110BimingEnMgy leV)Fig. 2. XPS spectrum of Be1s of each Be samplebefore/after the corrosion test.Beryllium has been utilized as a moderator and/orreflector in a number of material testing reactors.Beryllium is also supposed to be widely used in fusionreactors as neutron multiplier and protective walls ofplasma facing components. It is important to perform thecharacterization of the different grade beryllium such as theproductivity, mechanical and chemical properties and theinteractions under water and/or gas environment. In thisstudy, three kinds of beryllium were prepared and corrosiontest of these beryllium samples were carried out for lifetime expansion under pure water.The properties of three kinds of beryllium samplesare shown in Table II). S-200F is the reference materialas the reflector in testing reactors. S-65H was tested due toits higher purity and better isotropy than S-200F, and 1-220H was tested due to its higher mechanical strength andbetter isotropy than S-200F. The corrosion test wascarried out under pure water at 50'C up to 8300 h. In thetest, water analysis was carried out during the corrosion testby the pH/conductivity meter. The surface interactions ofthese beryllium samples were also evaluated by X-RayDiffraction (XRD), X-ray Photoelectron Spectroscopy(XPS) and electric conductivity measurement.In the corrosion test, the pH of water in the vesselinstalled Be samples was almost 6 at a stationary value.The conductivity increased gently and the value was about400flS/m. During the corrosion test, the white productwas generated on the surface of each Be sample. The(100), (002) and (l01) peaks of beryllium were observed ineach Be sample. These peaks of each Be sampledecreased after the corrosion test and the decrease of peaksin S-200F was larger than that in I-220H.The weight change of S-200F was larger than that ofI-220H after the corrosion test. Figure 1 shows thechange of electric conductivity of each Be sample. Ratioof electric conductivity of S-200F was larger than that of S-65H and I-220H. The conductivity of I-220H was almostno change. From these results, the corrosion propertieswere evaluated by the measurements of weight change andelectric conductivity and influenced by the content of BeOand grain size of each Be sample.The XPS spectrum of Be1s of each Be samplebefore/after the corrosion test is shown in Fig.2. One peakin about 112eV was observed in each Be sample before thecorrosion test. On the other hand, two peaks in about 110and 112eV were observed after the corrosion test. From theresult, the surface change of each Be sample occurred afterthe corrosion test.535§68. Basic Study on Surface Chemical Combination between Beryllium Metal and Hydrogen Isotope Gas (II)Ito, M., Kitagishi, S., Hanawa, Y., Tsuchiya, K. (JAEA),  Hatano, Y., Matsuyama, M. (Univ. Toyama),  Nagasaka, T., Hishinuma, Y.

Basic Study on Surface Chemical Combination between Beryllium Metal and Hydrogen Isotope Gas (II)

Basic Study on Surface Chemical Combination between Beryllium Metal and Hydrogen Isotope Gas (II)

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