Issue34

Y. Nakai et alii, Frattura ed Integrità Strutturale, 34 (2014) 246-254; DOI: 10.3221/IGF-ESIS.34.26 250 (A) x y z (C) (B) Rolling direction Contact ball (a) N = 1.100 × 10 7 cycles Observation direction (A) (B) (C) x y z x z y Rolling direction Contact surface 50 m  Inclusions ■ Crack (A) (B) (A) (B) 50 m  50 m  (C) x y z x z y (C) x y z x z y (b) N = 1.168 × 10 7 cycles (c) N f = 1.295 × 10 7 cycles ■ Crack ■ Flaking Figure 6 : 3D-images of crack and inclusion. Figure 7 : SEM micrograph of surface crack ( p max = 5.39 GPa, N = 6.00×10 6 cycles).