Issue 49

Y. Chang et alii, Frattura ed Integrità Strutturale, 49 (2019) 1-11; DOI: 10.3221/IGF-ESIS.49.01

60

A1, d = 54 nm B1, d = 48 nm B2, d = 73 nm

50

40

30

20

Frequency, %

10

0 20 40 60 80 100 120 140 160 0

Grain Size, nm

Figure 4: Distribution of grain size underneath FGA surface for samples A1, B1 and B2.

1000

A1, t = 315 nm B1, t = 435 nm B2, t = 386 nm

800

600

400

200

Thickness of Nanograin Layer, nm

0

0

2

4

6

8

10

Distance along Crack Growth Path, μm

Figure 5: Thickness of nanograin layer along crack growth path underneath FGA surface for samples A1, B1 and B2.

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8

A1, RB, R =  1 B1, UL, R =  1 B2, UL, R =  0.5

d* , Normalized Quantity

4

6

8

10

12

14

16

Distance along Crack Growth Path, μm

Figure 6: Distribution of normalized quantity d * versus crack growth path for samples A1, B1 and B2.

6