The permeability was measured for pressure differentials ranging from 0.6 to 12000Pa and for temperatures of between 497 and 933K. A square-root dependence of the permeability upon the driving pressure was observed at higher pressures. The data could be described by:

P (μmol/m s kPa½) = 2.698 x 100 exp[-59.405(kJ/mol)/RT]

The pressure at which this relationship no longer applied depended upon the H purity.

E.H.Van Deventer, V.A.Maroni: Journal of Nuclear Materials, 1980, 92[1], 103-11

 

Table 107

Permeation Parameters for AISI321

 

Cold-Rolling (%)

α' (%)

Po (mol/msMPa½)

E (kJ/mol)

0

0

2.44 x 10-4

62.70

21

9.3

9.24 x 10-5

53.50

34

26

2.06 x 10-4

54.40

54

51

1.22 x 10-4

46.88

65

55

6.75 x 10-5

44.26