Exposure of bolt-loaded DCB specimens to marine atmosphere and artificial sea water environments showed that YX-oriented stress corrosion crack growth in 7075 alloy plate is extremely slow, and is not greatly dependent on temper condition. Apparent ‘threshold’ stress intensities (KIsce)are about 25 MPa√m compared to ZX values which rangefrom about 5 (-T651 temper) to 23 (-T7351 temper)MPa√m Most of the crack growth in YX-oriented DCB specimens occurs in a plane normal to the precrack (ZX-oriented). These secondary cracks are presumably caused by the transverse tensile stress acting at the crack tip, and assume a size and shape similar to that of the plastic zone at this location.
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References
1.
BrownB. F., Metall. Rev., 1968, 13, 171
2.
HyattM. V., Corrosion, 1970, 26, 487
3.
SpeidelM.0., ‘The Theory of Stress Corrosion Cracking in Alloys’. Ed.ScullyJ. C.1971, p. 289 (Brussels: NATO)
4.
SpeidelM.0., Metal!. Trans., 1975, 6A, 631
5.
SprowlsD.0., Summerson, T. J., Ugiansky, G. M., Epstein, S. G., & Craig, H. L., ASTM STP 610, P.3(1976)
