The behavior of -phase solid solutions exhibited the entire range of characteristics of anomalous diffusion in group-IVb elements. Arrhenius plots of the interdiffusion coefficients (table 91) indicated the operation of a mono-vacancy diffusion mechanism. A temperature dependence of the migration energy resulted from softening of the phonon LA(2/3)<111> mode. A curvature of the Arrhenius plots was attributed to the temperature-dependent T1(1/2)<110> mode. At temperatures of between 1000 and 1900C, the interdiffusion coefficients of these alloys could be assumed to be independent of the composition.

D.Ansel, A.Margottet, M.Boliveau, J.Debuigne: Scripta Materialia, 1996, 34[5], 749-55

 

 

 

Table 91

Interdiffusion in the Hf-Zr System

 

Temperature (C)

Zr (at%)

D (cm2/s)

1820

10

1.01 x 10-7

1900

10

1.38 x 10-7

1820

15

1.03 x 10-7

1900

15

1.39 x 10-7

1820

20

1.05 x 10-7

1900

20

1.39 x 10-7

1820

25

1.07 x 10-7

1900

25

1.38 x 10-7

1600

30

4.41 x 10-8

1700

30

5.49 x 10-8

1820

30

1.08 x 10-7

1900

30

1.40 x 10-7

1600

35

4.46 x 10-8

1700

35

6.08 x 10-8

1820

35

1.09 x 10-7

1900

35

1.41 x 10-7

1500

40

2.45 x 10-8

1600

40

4.50 x 10-8

1700

40

6.29 x 10-8

1820

40

1.10 x 10-7

1900

40

1.42 x 10-7

1500

45

2.53 x 10-8

1600

45

4.56 x 10-8

1700

45

6.48 x 10-8

1820

45

1.10 x 10-7

1900

45

1.45 x 10-7

1500

50

2.59 x 10-8

1600

50

4.60 x 10-8

1700

50

6.57 x 10-8

1820

50

1.10 x 10-7

1400

55

1.30 x 10-8

1500

55

2.79 x 10-8

1600

55

4.73 x 10-8

1700

55

6.58 x 10-8

1820

55

1.11 x 10-7

1400

60

1.33 x 10-8

1500

60

2.80 x 10-8

1600

60

4.84 x 10-8

1700

60

6.46 x 10-8

1820

60

1.12 x 10-7

1300

65

7.53 x 10-9

1400

65

1.34 x 10-8

1500

65

2.68 x 10-8

1600

65

4.79 x 10-8

1700

65

6.35 x 10-8

1820

65

1.13 x 10-7

1300

70

7.55 x 10-9

1400

70

1.34 x 10-8

1500

70

2.66 x 10-8

1600

70

4.67 x 10-8

1700

70

6.36 x 10-8

1820

70

1.14 x 10-7

1200

75

4.11 x 10-9

1300

75

7.62 x 10-9

1400

75

1.41 x 10-8

1500

75

2.71 x 10-8

1600

75

4.55 x 10-8

1700

75

6.37 x 10-8

1820

75

1.15 x 10-7

1200

80

4.46 x 10-9

1300

80

7.82 x 10-9

1400

80

1.51 x 10-8

1500

80

2.69 x 10-8

1600

80

4.45 x 10-8

1700

80

6.39 x 10-8

1820

80

1.18 x 10-7

1100

85

2.36 x 10-9

1200

85

4.46 x 10-9

1300

85

8.17 x 10-9

1400

85

1.51 x 10-8

1500

85

2.56 x 10-8

1600

85

4.39 x 10-8

1700

85

6.45 x 10-8

1820

85

1.21 x 10-7

1100

90

2.78 x 10-9

1200

90

4.45 x 10-9

1300

90

8.42 x 10-9

1400

90

1.38 x 10-8

1500

90

2.49 x 10-8

1600

90

4.42 x 10-8

1700

90

6.46 x 10-8

1820

90

1.22 x 10-7

1000

95

9.60 x 10-10

1100

95

2.86 x 10-9

1200

95

4.55 x 10-9

1300

95

9.93 x 10-9

1400

95

1.34 x 10-8

1500

95

2.55 x 10-8

1600

95

4.52 x 10-8

1700

95

6.79 x 10-8

1820

95

1.22 x 10-7