Issue34

Y. Nakai et alii, Frattura ed Integrità Strutturale, 34 (2014) 246-254; DOI: 10.3221/IGF-ESIS.34.26

(B)

(A)

Rolling direction

Observation direction

(A)

Rolling direction

■ Crack

Contact ball

y

(B)

y

y

x

z

x

z

(C)

(C)

Contact surface

50 m 

x

Inclusions

z

(a) N = 6.00 × 10 6 cycles

(B)

(B)

(A)

(A)

■ Crack

■ Crack

y

y

y

y

z

z

x

x

(C)

(C)

50 m 

50 m 

x

x

z

z

(c) N = 7.10 × 10 6 cycles

(b) N = 6.80 × 10 6 cycles

(B)

(B)

(A)

(A)

■ Crack

y

y

y

y

z

x

z

x

(C)

(C)

■ Flaking

50 m 

x

x

50 m 

z

z

(e) N f = 7.67 × 10 6 cycles

(d) N = 7.50 × 10 6 cycles

Figure 9 : 3D-images of cracks and inclusions.

252