It was pointed out that the use of implanted mass-separated carrier-free 105Ag radio-tracers improved the sensitivity of measurements of grain-boundary penetration profiles. By this means, the grain-boundary self-diffusion coefficient was directly deduced from experiments which had been performed under type-C kinetics conditions (tables 3 and 4). Upon multiplying the grain-boundary diffusivity (tables 5 and 6) by a grain-boundary width of 0.5nm, the results were found to be in agreement with the diffusivities which had been measured under type-B kinetic conditions at temperatures of between 911 and 540K and had been extrapolated to temperatures of between 455 and 353K. The dislocation density was directly determined from the near-surface portion of the type-C diffusion profiles. Analysis of the results (table 7) indicated a dislocation core diameter of about 0.5nm.

J.Sommer, C.Herzig: Journal of Applied Physics, 1992, 72[7], 2758-66

 

 

 

Table 3

Volume Diffusivity of 110mAg in Ag Polycrystals

 

Temperature (K)

D (m2/s)

911

7.56 x 10-16

776

1.53 x 10-17

751

6.43 x 10-18

723

2.23 x 10-18

701

9.18 x 10-19

672

2.60 x 10-19

622

2.27 x 10-20

565

8.29 x 10-22

564

7.78 x 10-22

560

6.00 x 10-22

554

4.05 x 10-22

544

2.06 x 10-22

537

1.26 x 10-22

497

5.91 x 10-24

478

1.19 x 10-24

452

9.43 x 10-26

424

5.03 x 10-27

423

4.64 x 10-27

394

1.29 x 10-28

 

 

 

Table 4

Volume Diffusivity of 105Ag in Ag Polycrystals

Temperature (K)

D (m2/s)

455

1.34 x 10-25

424

5.03 x 10-27

394

1.29 x 10-28

353

3.14 x 10-31

 

 

 

Table 5

Grain Boundary Diffusivity of 110mAg in Ag Polycrystals

 

Temperature (K)

D (m3/s)

911

1.82 x 10-19

776

2.49 x 10-20

751

1.81 x 10-20

723

1.45 x 10-20

701

9.12 x 10-21

672

6.88 x 10-21

622

2.04 x 10-21

565

8.00 x 10-22

564

4.87 x 10-22

560

5.40 x 10-22

554

5.17 x 10-22

544

3.40 x 10-22

537

2.49 x 10-22

497

5.92 x 10-23

478

1.09 x 10-23

452

1.89 x 10-24

424

1.77 x 10-24

423

1.46 x 10-24

394

6.52 x 10-26

 

 

 

Table 6

Grain Boundary Diffusivity of 105Ag in Ag Polycrystals

 

Temperature (K)

D (m2/s)

455

2.57 x 10-14

424

2.24 x 10-14

394

3.84 x 10-15

353

1.16 x 10-16

 

 

 

Table 7

Pipe Diffusivity of Ag Isotopes in Ag Polycrystals

Temperature (K)

Isotope

D (m2/s)

455

105Ag

5.26 x 10-15

424

105Ag

4.64 x 10-15

424

110mAg

4.03 x 10-15

394

105Ag

1.12 x 10-15

394

110mAg

3.36 x 10-15