Page 89 - Biaxial Multiaxial Fatigue and Fracture

74 h! ISOBE AND S. SAKURAI

Fig. 15. Grain boundary where the crack in Fig. 10 initiated after the specimen had been heated.

i . i b '
i
,J
I

, 50pm ,

(a) Base metal, $=- 1 .OO, A%,=0.7%

i

i
i
i
I
, 50pm , I

(b) Axially welded specimen, $=-1 .OO, A&,,=0.7%
Fig. 16. Surface cracks and oxide spikes.