Effect of Microstructure on Hydrogen Diffusion in Weld and API X52 Pipeline Steel Base Metals under Cathodic Protection

Table 7

Data obtained from analysis of the hydrogen permeability plot for all samples of API X52 steel.

Sample	(A)	(s)	Effective diffusion coefficient () (×10^−4 mm^2·s^−1)
			Time Lag		Breakthrough		Fourier
			(s)		(s)
BM	2.983	12300	2610	2.554	590	4.460	4.902
WM	2.045	16850	3900	1.709	810	3.249	3.010
ABM	4.456	4680	1020	6.536	310	8.489	15.040
QBM	2.751	11160	3180	2.096	545	4.829	4.025

required for permeation current stabilization ().