This paper describes the process of hydrogen diffusion in API 5L X65 and ASTM A182 F22 steels with three different metallurgical microstructures (quenched and tempered, quenched and annealed) by an electrochemical technique which is a modified Devanathan and Stachurski's cell. The analysis of experimental results compares different measurement methods for hydrogen diffusion coefficients: 1) charge method; 2) partial charge and partial discharge method; 3) discharge method. For the steel, cathodically polarized in acidic medium (pH z 4.2), the less dispersed and more meaningful results are obtained by partial charge and partial discharge method after about one hundred hours of polarization, i.e., when a stationary regime was reached. The discharge method, carried out after one hundred hours of polarization, provides analogous results by extrapolation of the experimental results obtained during the initial phase of hydrogen desorption. The hydrogen diffusion coefficients measured would appear dependent only on the hydrogen migration processes in the crystal lattice regular sites and corresponding values DL increase as follows: quenched < quenched and tempered < annealed.
Hydrogen diffusion into three metallurgical microstructures of a CeMn X65 and low alloy F22 sour service steel pipelines
FALLAHMOHAMMADI, EHSAN;BOLZONI, FABIO MARIA;FUMAGALLI, GABRIELE;LAZZARI, LUCIANO
2014-01-01
Abstract
This paper describes the process of hydrogen diffusion in API 5L X65 and ASTM A182 F22 steels with three different metallurgical microstructures (quenched and tempered, quenched and annealed) by an electrochemical technique which is a modified Devanathan and Stachurski's cell. The analysis of experimental results compares different measurement methods for hydrogen diffusion coefficients: 1) charge method; 2) partial charge and partial discharge method; 3) discharge method. For the steel, cathodically polarized in acidic medium (pH z 4.2), the less dispersed and more meaningful results are obtained by partial charge and partial discharge method after about one hundred hours of polarization, i.e., when a stationary regime was reached. The discharge method, carried out after one hundred hours of polarization, provides analogous results by extrapolation of the experimental results obtained during the initial phase of hydrogen desorption. The hydrogen diffusion coefficients measured would appear dependent only on the hydrogen migration processes in the crystal lattice regular sites and corresponding values DL increase as follows: quenched < quenched and tempered < annealed.File | Dimensione | Formato | |
---|---|---|---|
PAPER IDROGENO 2014 INT JOURNAL hYDROGEN ENERGY.pdf
Accesso riservato
:
Post-Print (DRAFT o Author’s Accepted Manuscript-AAM)
Dimensione
3.73 MB
Formato
Adobe PDF
|
3.73 MB | Adobe PDF | Visualizza/Apri |
Hydrogen diffusion into three metallurgical microstructures_11311-843531_Bolzoni.pdf
accesso aperto
:
Post-Print (DRAFT o Author’s Accepted Manuscript-AAM)
Dimensione
3.44 MB
Formato
Adobe PDF
|
3.44 MB | Adobe PDF | Visualizza/Apri |
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.