Hydrogen degradation and its mechanism in fcc metals for high-pressure hydrogen storage tanks

• Autorzy: Takai K.
• Języki publikacji: EN

Abstrakty

EN

Metals high resistant to hydrogen degradation have been required, since hydrogen pressure in a storage tank for fuel cell vehicle varies from 35 MPa to 70 MPa, and that in the tank for hydrogen refueling station increases to above 100 MPa. Fcc metals used under the high-pressure hydrogen for fuel-cell constituent materials such as SUS 316L and Inconel 625 have been prepared. Two principal aspects regarding the fcc metals are presented here: (1) to find out the condition of electrolytic hydrogen charging corresponding to various hydrogen pressures, since the charging under high-pressure hydrogen is much dangerous and more expensive than the electrolytic hydrogen charging, and (2) to clarify the degradation susceptibility mechanism using slow strain rate technique (SSRT). The fcc metals have been charged with the electrolytic and high-pressure hydrogen, then the hydrogen content and trapping states have been analyzed. The electrolytic hydrogen charging enables to substitute high-pressure hydrogen atmosphere such as hydrogen refueling station using Sieverts rule, since trapping states of hydrogen absorbed in electrolytic conditions correspond to those in high-pressure conditions. The strain to failure of Inconel 625 bas been critically dependent on hydrogen content and decreased with increasing hydrogen content. In contrast, the strain to failure of SUS 316L bas remained constant regardless of hydrogen content. The vacancy and vacancy clusters enhanced by interaction between stress and hydrogen play an important role in hydrogen degradation of Inconel 625.

Słowa kluczowe

EN

hydrogen absorbing materials; degradation; thermal desorption analysis; lattice defects; fcc materials

• Wydawca: Politechnika Gdańska
• Czasopismo: Advances in Materials Science
• Rocznik: 2007
• Tom: Vol. 7, nr 1(11)
• Strony: 205--210
• Opis fizyczny: Bibliogr. 3 poz., rys., tab.

Twórcy

autor

Takai K.

• Department of Mechanical Engineering, Sophia University, Tokyo, Japan

Bibliografia

• [1] Nagumo M., Nakamura M. and Takai K.: Hydrogen thermal desorption relevant to delayed-fracture susceptibility of high-strength steels. Metall. Mater. Trans. A, 32A (2001), pp.339-347.
• [2] Takai K. and Watanuki R: Hydrogen in trapping states innocuous to environmental degradation of high-strength steels. ISIJ Intemational,VoI.43, (2003), pp.520-526.
• [3] Takai K., Chiba Y., Noguchi K. and Nozue A.: Visualization of hydrogen desorption process from ferrite, pearlite and graphite by secondary ion mass spectrometry. Metall. Mater. Trans. A, 33A (2002), pp.2659-2665.