Search Sites

Zairyo-to-Kankyo Vol. 70 (2021), No. 2

ISIJ International
belloff
ONLINE ISSN: 1881-9664
PRINT ISSN: 0917-0480
Publisher: Japan Society of Corrosion Engineering

Backnumber

  1. Vol. 73 (2024)

  2. Vol. 72 (2023)

  3. Vol. 71 (2022)

  4. Vol. 70 (2021)

  5. Vol. 69 (2020)

  6. Vol. 68 (2019)

  7. Vol. 67 (2018)

  8. Vol. 66 (2017)

  9. Vol. 65 (2016)

  10. Vol. 64 (2015)

  11. Vol. 63 (2014)

  12. Vol. 62 (2013)

  13. Vol. 61 (2012)

  14. Vol. 60 (2011)

  15. Vol. 59 (2010)

  16. Vol. 58 (2009)

  17. Vol. 57 (2008)

  18. Vol. 56 (2007)

  19. Vol. 55 (2006)

  20. Vol. 54 (2005)

  21. Vol. 53 (2004)

  22. Vol. 52 (2003)

  23. Vol. 51 (2002)

  24. Vol. 50 (2001)

  25. Vol. 49 (2000)

  26. Vol. 48 (1999)

  27. Vol. 47 (1998)

  28. Vol. 46 (1997)

  29. Vol. 45 (1996)

  30. Vol. 44 (1995)

  31. Vol. 43 (1994)

  32. Vol. 42 (1993)

  33. Vol. 41 (1992)

  34. Vol. 40 (1991)

Zairyo-to-Kankyo Vol. 70 (2021), No. 2

Corrosion and Microbe

Yasuko Yao

pp. 31-31

Bookmark

Share it with SNS

Article Title

Corrosion and Microbe

The Role of Micro Pit in the Initiaion Process of Crevice Corrosion of SUS304 Stainless Steel in Aqueous Chloride Solution

Akira Nagaoka, Kiyomi Nose, Kana Nokami, Haruhiko Kajimura

pp. 32-39

Abstract

On a free surface not having crevice structures, micro pits on the order of several μm in diameter that are repassivated immediately are called meta-stable pits. The role of the micro pit as an initiation site of crevice corrosion was examined by comparing the meta-stable pitting corrosion potential (V'cMS) of SUS304 steel measured on the free surface with the critical potential for crevice corrosion (VCREV). VCREV presented the similar value to V'cMS. It was also revealed that micro pits, as well as SUS304 stainless steel surface, were hard to be repasivated at pH≥2.0, meaning that micro pits can be initiation sites of crevice corrosions. Investigating Cl concentration and pH dependencies on each potential, the influences of these factors were also examined in terms of the contribution to a crevice corrosion initiation. Cl ions, which have V'cMS and VCREV less noble, will directly contribute to a crevice corrosion initiation by facilitating micro pit initiations. pH decrease accelerating a passivation dissolution would promote a crevice corrosion initiation indirectly by increasing a Cl migration into a crevice structure.

Bookmark

Share it with SNS

Article Title

The Role of Micro Pit in the Initiaion Process of Crevice Corrosion of SUS304 Stainless Steel in Aqueous Chloride Solution

Development of Corrosion Depth Evaluation Method in Steel Pipe by Acoustic Emission Method

Takuya Kurihara, Matsuo Takuma, Taro Kono, Kaori Numata

pp. 40-46

Abstract

Steel pipes used for the transportation of materials, such as tap water and gas, can leak due to corrosion. Therefore, monitoring the conditions of these pipes is significantly important. In this study, an inspection and monitoring method for evaluating the corrosion losses of steel pipes was developed using the acoustic emission (AE) method. First, steel pipes with different corrosion losses were installed, and AE monitoring was performed for one month. Corrosion loss was evaluated using an intensity ratio representing the maximum amplitude of wavelet coefficient of the longitudinal and flexural modes in the AE signals (i.e., AE wavelet coefficient ratio) resulting from the fractures caused by rust. The AE wavelet coefficient ratio changed with increasing corrosion depth, and a relationship between the corrosion loss and the change in the AE wavelet coefficient ratio was observed. This result indicated that the corrosion loss could be evaluated using AE monitoring. Next, a thermal cycle was applied to the corroded areas of the steel pipes, and the AE signals were monitored. The fracturing resulting from the rust produced several AE signals, and the AE wavelet coefficient ratio changed depending on the corrosion depth. Therefore, the corrosion loss could also be evaluated by applying the AE wavelet coefficient ratio to an AE measurement test with a thermal cycle.

Bookmark

Share it with SNS

Article Title

Development of Corrosion Depth Evaluation Method in Steel Pipe by Acoustic Emission Method

Development of Quantitative Analytical Program for Corrosion Sensor Data

Norikazu Fuse, Atsushi Naganuma, Yoshiharu Shumuta, Jun-ichi Tani, Yasuhiko Hori

pp. 47-54

Abstract

The analysis algorithm named ACCESS was developed for galvanic sensor data, in order to qualitatively evaluate the corrosion rate. The analysis uses record of humidity along with the sensor data to extract outlier galvanic outputs that arise during rainfall. The quantitativeness of the analysis was verified using the field data observed in an exposure site and 19 transmission towers along a Japanese coastal area. The corrosion rates estimated from the sensor signals and measured using standard coupons were found to be in good agreement. The high corrosion season and its environmental features were extracted from the results of the short-term analysis of the corrosion rate, especially in the season of storm approach and snowfall.

Bookmark

Share it with SNS

Article Title

Development of Quantitative Analytical Program for Corrosion Sensor Data

You can use this feature after you logged into the site.
Please click the button below.

Advanced Search

Article Title

Author

Abstract

Journal Title

Year

Please enter the publication date
with Christian era
(4 digits).

Please enter your search criteria.