著者

鹿毛 勇 高阪 廣作 松本 雅充 野村 広正 岩井 正敏 磯部 誠 辻川 茂男

出版者

一般社団法人日本建築学会

雑誌

学術講演梗概集. C-1, 構造III, 木質構造, 鉄骨構造, 鉄骨鉄筋コンクリート構造 (ISSN:1341447X)

巻号頁・発行日

vol.2000, pp.1037-1038, 2000-07-31

著者

貴堂 高徳 辻川 茂男

出版者

社団法人日本鉄鋼協会

雑誌

鐵と鋼 : 日本鐡鋼協會々誌 (ISSN:00211575)

巻号頁・発行日

vol.75, no.8, pp.1332-1337, 1989-08-01

被引用文献数

1

---

Critical conditions to repassivate growing crevice corrosion in terms of electrode potential, E_R, temperature, T_R, and NaCl concentration, C_<NaCl, R>, were determined for metal/metal-crevice of ASTM Grade 12 (G 12 Ti) and Ti-x(=0&acd;2%)Ni-y(=0&acd;0.4%) Mo alloys. G 12 Ti with 0.8%Ni and 0.3% Mo has more noble E_R values than commercially pure Titanium (C.P. Ti) and this tendency is more enhanced in lower concentrations of NaCl solutions. G 12 Ti is predicted to be resistant to crevice corrosion in solutions containing as high as 9% NaCl at 100℃, which is markedly higher than 1% NaCl or less as the highest concentration for C.P. Ti to be resistant at the temperature. E_R value for Ti-xNi-yMo alloy depends almost on Ni content. Sufficiently noble value of E_R is attained for the alloys with Ni contents over 0.2%. The beneficial effect of Ni could be explained from formation of Ti_2Ni which works as Pd does in Ti-0.15 Pd alloy. C_<NaCl, R> depends not only on Ni content but also on Mo content. It decreases with increasing Mo content in the range from 0 to 0.1&acd;0.2%, above which C_<NaCl, R> increases with increasing Mo content. This shows beneficial effect of Mo combined with Ni. Based on the results of Ti-xNi-yMo alloy, characteristics of G 12 Ti are found to be accounted for approximately through its contents of Ni and Mo.

著者

兒島 洋一 岸元 努 辻川 茂男

出版者

Japan Society of Corrosion Engineering

雑誌

Zairyo-to-Kankyo (ISSN:09170480)

巻号頁・発行日

vol.45, no.5, pp.305-314, 1996-05-15 (Released:2009-11-25)

参考文献数

25

被引用文献数

1

---

The rate of uniform corrosion, the likelihood of pitting and crevice corrosion for aluminum, Al, in white wine were investigated in this paper. In commercial wines, the K2S2O5 is commonly added to induce free-SO2 which reduces the dissolved oxygen and acts as a fungicide in the wine. The spontaneous electrode potential of Al, ESP, in a deaerated wine containing less than 1ppm of free-SO2, at 25°C was measured to be about -600mV vs. SCE. Since the K2S2O5 is an oxidizing agent for the Al, the ESP was ennobled with the addition of K2S2O5 reaching -520mV with a concentration of 1000ppm K2S2O5. The uniform corrosion rate was measured to be 13μm/y at 25°C and this rate was found to depend on the temperature with an activation energy of 42kJ/mol. However, this rate was found to have no dependency on the electrode potential within the ESP range. The critical pitting potential, VC, PIT, measured in the wine containing 25ppm of Cl- was -370mV which was more noble than the ESP, and the pitting corrosion can not occur. The repassivation potential for the growing crevice corrosion, ER, CREV, was measured to be -530mV. It was also found that this potential does not depend on either the temperature or the concentration of K2S2O5. It was observed that the ESP became more noble than the ER, CREV with the addition of 800ppm K2S2O5 at 25°C. At a lower temperature, however, the ESP became more noble than the ER, CREV when a lesser amount of K2S2O5 were added. An effective method to decrease the rate of uniform corrosion is to reduce the holding temperature; however, to effectively prevent the crevice corrosion at these lower temperatures, the K2S2O5 concentration must be kept below 100ppm.