ばね鋼材の実使用環境及びラボ試験環境から侵入する水素量の推定と昇温脱離式ガスクロで測定される拡散性水素量の解釈方法

• Published in: Transaction of Japan Society of Spring Engineers Vol. 2018; no. 63; pp. 27 - 39
• Main Authors: 石黒, 康英, 藤村, 和樹, 大塚, 真司, 小林, 聡雄
• Format: Journal Article
• Language: Japanese
• Published: Tokyo 日本ばね学会 31.03.2018; Japan Science and Technology Agency
• Subjects: Accelerated corrosion; Bainite; Corrosion; Corrosion environments; Desorption; Diffusive hydrogen; FeOOH; Gas chromatograph; Gas chromatography; High strength steel; High strength steels; Hydrogen; Hydrogen embrittlement; Hydrogen uptake; Laboratories; Martensite; Rust; Spectrum analysis; Spring steel; TDS; Thermo-Desorption Spectroscopy
• ISSN: 0385-6917; 1348-1479
• DOI: 10.5346/trbane.2018.27

The theme of this paper is the hydrogen uptake in high-strength steel mainly for spring and stabilizer of automobile, when used in actual use environment and/or corroded in laboratory-simulating accelerated corrosion environment. In addition, this report gives a new interpretation to diffusive hydrogen concentration measured with Gas-Chromatograph-based Thermo-Desorption-Spectroscopy. When hydrogen in corroded steel (bcc-based ferrite, bainite or martensite) is measured after removing corrosion layer, hydrogen signal often appears at 300 to 400℃, in addition to both diffusive hydrogen signal at below 200℃ and non-diffusive hydrogen signal at over 400℃. However, the hydrogen signal at 300 to 400℃ has not been defined correctly, and it has been regarded as a long-standing unclear problem. Through experimental data and evidence, it is shown that the hydrogen peaks at 300 to 400℃ is based on inevitably-remaining deeply-rooted rust of FeOOH which cannot be removed perfectly from corroded steel sample even with a careful hand-polishing. The hydrogen spectrum appearing at around 300 to 400℃ has no relation to both diffusive hydrogen and non-diffusive hydrogen, and it is generated inside Gas Chromatograph, and therefore, it is not involved with hydrogen embrittlement at all.