A 20Cr/25Ni/Nb stabilized austenitic steel has been tested in push/pull, high-strain fatigue between 650 and 900°C in air. The mode of crack nucleation and the processes that accompany it have been studied; the results show that the evolution of a crack is a relatively complex phenomenon involving the environment, plastic flow at the surface, the creation of a new autonomous “grain” at the crack nucleus, and the eventual development of an embryonic crack.
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References
1.
SumnerG., “Thermal and High Strain-Fatigue”, p. 295. 1967: London (Inst. Metals).
2.
WoodW. A., McK. CouslandS., and SargantK. R., Acta Met., 1963, 11, 643.
3.
RitterD. L. and GrantN. J., Ref. 1, p. 80.
4.
CookT. R., paper presented at Conference on“The Physics and Mechanics of Metal Fatigue ”, Bristol, 1966. (Inst. Physics).
5.
LairdC. and SmithG. C., Phil. Mag., 1962, 7, 847.
6.
McEvilyA. J. and BoettnerR. C., Acta Met., 1963, 11, 725.
