Chemical diffusion in this system was studied, at temperatures ranging from 1200 to 1500K, by using pure metal diffusion couples. The concentration penetration profiles were determined by means of electron probe microanalysis, and the diffusion coefficients  (tables 160 and 161) were evaluated by using the Boltzmann-Matano method. It was found that the chemical diffusivity at a given composition and temperature could be described by:

D (m2/s) = 2.75 x 10-5exp[-4.14CTi] exp[-{212.647 + 68.16CTi}(kJ/mol)/RT]

The data were explained in terms of the Vignes-Birchenall relationship.

G.B.Kale, R.V.Patil: Materials Transactions, 1994, 35[7], 439-44

 

 

 

Table 160

Chemical Diffusion Coefficients for the Ti-Mo System

 

Ti (at%)

Temperature (K)

D (m2/s)

10

1199

2.3 x 10-14

20

1199

2.5 x 10-14

30

1199

3.7 x 10-14

40

1199

4.0 x 10-14

50

1199

5.0 x 10-14

60

1199

6.4 x 10-14

70

1199

8.9 x 10-14

80

1199

1.7 x 10-13

90

1199

2.1 x 10-13

10

1217

3.2 x 10-14

20

1217

4.2 x 10-14

30

1217

4.3 x 10-14

40

1217

4.7 x 10-14

50

1217

6.0 x 10-14

60

1217

7.5 x 10-14

70

1217

1.03 x 10-13

80

1217

1.82 x 10-13

90

1217

2.42 x 10-13

10

1330

1.30 x 10-13

20

1330

1.90 x 10-13

30

1330

2.00 x 10-13

40

1330

2.30 x 10-13

50

1330

2.90 x 10-13

60

1330

3.60 x 10-13

70

1330

4.50 x 10-13

80

1330

7.00 x 10-13

90

1330

9.20 x 10-13

10

1364

2.20 x 10-13

20

1364

2.20 x 10-13

30

1364

2.30 x 10-13

40

1364

3.00 x 10-13

50

1364

4.30 x 10-13

60

1364

5.00 x 10-13

70

1364

6.20 x 10-13

80

1364

9.60 x 10-13

90

1364

1.22 x 10-12

10

1479

8.00 x 10-13

20

1479

1.10 x 10-12

30

1479

1.20 x 10-12

40

1479

1.30 x 10-12

50

1479

1.50 x 10-12

60

1479

1.80 x 10-12

70

1479

2.10 x 10-12

80

1479

2.70 x 10-12

90

1479

3.70 x 10-12

10

1518

1.70 x 10-12

20

1518

2.00 x 10-12

30

1518

2.05 x 10-12

40

1518

2.10 x 10-12

50

1518

2.20 x 10-12

60

1518

2.80 x 10-12

70

1518

3.30 x 10-12

80

1518

3.90 x 10-12

90

1518

5.50 x 10-12

 

 

 

Table 161

Chemical Diffusion Parameters for the Ti-Mo System

 

C (at%)

Do (m2/s)

Q (kJ/mol)

10

227.0

207.2

20

81.3

194.5

30

100

192.5

40

44.0

185.2

50

31.0

179.1

60

33.0

177.5

70

19.0

168.9

80

4.9

148.7

90

9.2

152.8