Crack Tip Plasticity Associated with Corrosion Assisted Fatigue.
Final rept. Jun 74-Dec 82,
SOUTHWEST RESEARCH INST SAN ANTONIO TX
Pagination or Media Count:
Measurement of the influence of water vapor in the environment on fatigue crack tip strains and stresses has been the objective of this program. In low-carbon steel, stresses in the plastic zone were deduced by imaging subcells formed during fatigue crack growth. Water vapor was found to lower the stress levels and decrease the size of the zone of stresses exceeding the yield value. Strains within the plastic zone and at the crack tip may be determined by the stereoimaging technique. For low-carbon steel, water vapor lowers the strains carried by the crack tip, and stresses computed from these strains agree well with those determined from measurement of subcell size. A manuscript is included in this report which describes the computational technique of converting strains to stresses.
- Properties of Metals and Alloys