Standard permeation equipment was used to study the effects of atomic ordering upon permeability and diffusivity (tables 23 and 24). Ordering took place at 350 to 380C, and resulted in lower H diffusivity and permeability coefficients than those expected by extrapolating from high-temperature data.

V.A.Goltsov, V.B.Vykhodets, P.V.Geld, T.A.Krylova: Fizika Metallov i Metallovedenie, 1970, 30[3], 657-9

 

 

Table 23

Parameters for H Diffusion in Cu3Au

 

Treatment

Temperature (C)

Do (cm2/s)

E (kcal/g-atom)

annealed (700C), sc 5C/h

430-600

5.14 x 10-4

10.25

annealed (700C), sc 5C/h

275-380

3.16 x 10-4

9.50

annealed (350C, 25-60h)

280-350

5.1 x 10-5

8.50

 

 

 

Table 24

Parameters for H Permeation in Cu3Au

 

Treatment

Temperature (C)

Po (cm mm/s atm½)

E (kcal/g-atom)

annealed (700C), sc 5C/h

430-600

2.42 x 10-1

18.6

annealed (700C), sc 5C/h

275-380

1.9 x 10-2

16.6

annealed (350C, 25-60h)

280-350

8.16 x 10-2

19.5