A pseudo-compliance method is discussed as a means of measuring fatigue crack lengths in BS 5447, ASTM E399.72 compact-tension specimens. A calibration curve for these specimens is obtained together with a relationship between pseudo-compliance and K, the stress intensity factor. This method is suitable for automatic crack monitoring and load control.
Get full access to this article
View all access options for this article.
References
1.
WadeE. H. R.LeeG. M. C.‘An ultrasonic fatigue crack growth monitor and load controller’, J. Strain Analysis197510, 159.
2.
SullivanA. M.Crack-length determination for the compact tension specimen using a crack opening displacement calibration Naval Research Laboratory, Washington DC, USA. Report No. 7888, June 1975.
3.
SullivanA. M.CrookerT. W.Evaluation of a fatigue crack opening displacement technique for crack length measurement National Research Laboratory, Washington DC, USA. Report No. 7912, September 1975.
4.
SullivanA. M.CrookerT. W.‘A crack opening displacement technique for crack growth rate testing—development and evaluation’, Engineering Fracture Mechanics, 19779, 159.
5.
6.
7.
WadeE. H. R.LeeG. M. C.‘The influence of mean stress on fatigue crack propagation in a quenched and tempered alloy steel’, J. Strain Analysis, 197712, 81.
8.
ClarkW. G.HudakS. J.‘Variability in fatigue crack growth rate fatigue testing’, J. Testing Evaluation19753, 454.
9.
WalkerE. F.MayM. J.Compliance functions for various types of test specimen geometry BISRA Report M6/E/307/67.
10.
VeermanC. C.MullerT.‘The location of the apparent rotation axis in notched bend testing’, Engineering Fracture Mechanics19724, 25.
11.
RobinsonT. N.TetelmanA. S.The critical crack-tip opening displacement and microscopic and macroscopic fracture criteria for metals University of California, Los Angeles, Report Eng. 7360, 1973.
InghamT.EganG. R.ElliotD.HarrisonT. C.‘The effect of geometry on the interpretation of COD test data’, Conference on practical applications of fracture mechanics to pressure vessel technology1971 (Instn Mech. Engrs.London).
14.
RiceJ. R.‘The mechanics of crack tip deformation and extension by fatigue’, ASTM STP 4151967, 247.
15.
LeeG. M. C.The use of a crack opening displacement gauge for measuring fatigue crack propagation rates University of Edinburgh, Mechanical Engineering Department Research Report, February 1977.