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X-ray Microtomography of Fatigue Crack Closure as a Function of Applied Load In Al-Li 2090 T8E41 Samples

Published online by Cambridge University Press:  10 February 2011

R. Morano ,
S.R. Stock ,
G.R. Davis  and
J.C. Elliott
R. Morano
Affiliation:
School of Materials Sci. & Eng. And Mechanical Properties Res. Lab., Georgia Institute of Technology, Atlanta, Ga 30332-0245, USA. stuart.stock@mse.gatech.edu
S.R. Stock
Affiliation:
School of Materials Sci. & Eng. And Mechanical Properties Res. Lab., Georgia Institute of Technology, Atlanta, Ga 30332-0245, USA. stuart.stock@mse.gatech.edu
G.R. Davis
Affiliation:
Dept. Of Biophysics in Relation to Dentistry, Queen Mary and Westfield College, London UK
J.C. Elliott
Affiliation:
Dept. Of Biophysics in Relation to Dentistry, Queen Mary and Westfield College, London UK
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Abstract

Crack closure is held to be responsible for very low fatigue crack growth rates in many alloys such as Al-Li 2090 T8E41, and early crack face contact during unloading or prolonged contact during loading seems to reduce the driving “force” for crack extension. High resolution x-ray computed tomography (i.e., microtomography) allows one to image the entire volumes of samples and to quantify opening as a function of applied load over the entire crack surface. Crack closure results are reported for a fatigue crack grown under load ratio R=0.1 in a compact tension sample of Al-Li 2090 T8E41; the crack was free to choose its path unconstrained by side-grooves which are normally used to suppress crack deflection. The inter-relationship between crack path, crack face contact and applied load level are discussed.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 591 , 1999 , 31
Copyright
Copyright © Materials Research Society 2000

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References

REFERENCES

1.Rao, K.T. Venkateswara, Yu, W. and Ritchie, R.O., Met Trans 19A (1988) 549–569.Google Scholar
2.Yoder, G.R., Pao, P.S., Imam, M.A., and Cooley, L.A., in Prio 5th Int Conf on Aloumion Lithum AlLoy., Sanders, T.H. Jr. and Starke, E.A Jr., Eds., (Mater Comp Eng Publ Ltd, Birmingham, UK, 1989) 1033–1041.Google Scholar
3.Pao, P.S., Imam, M.A., Cooley, L.A. and Yoder, G.R., Scr Met 23 (1989) 1455–1460.Google Scholar
4.Yoder, G.R., Pao, P.S., Imam, M.A. and Cooley, L.A., Scr Met 22 (1988) 1241–1244.Google Scholar
5.Haase, J.D., “Microbeam Diffraction Mapping of Microtexture in Al-Li 2090 T8E41,” MS Thesis, Georgia Institute of Technology, 1998.Google Scholar
6.Haase, J.D., Guvenilir, A., Witt, J.R. and Stock, S.R., Acta Mater 46 (1998) 4791–4799.Google Scholar
7.Haase, Jake D., Guvenilir, Abbas, Witt, Jason R., Langøy, Morten A. and Stock, Stuart R., in Mixed-Mode Crak Behavior. ASTM STP 1359 (1999) 160–173.Google Scholar
8.Christensen, R.H., Appl Mater Res October (1963) 207–210.Google Scholar
9.Elber, W., in Damage Tolerance in Aircraft Structures. ASTM STP 486 (1971) 230–242.Google Scholar
10.Ritchie, R.O., in Fatigu Thresholds. Backland, J., Blom, A. and Beevers, C.J., Eds., (Eng Adv Serv, Warley, UK, 1981) 503–526.Google Scholar
11.Ritchie, R.O., Mater Sci Eng A 103 (1988) 15–28.Google Scholar
12.Guvenilir, A., Breunig, T.M., Kinney, J.H. and Stock, S.R., Acta Mater 45 (1997) 1977–1987.Google Scholar
13.Guvenilir, A. and Stock, S. R., Fatigue Fracture Eng Mater Structures 21 (1998) 439–450.Google Scholar
14.Guvenilir, A., Breunig, T.M., Kinney, J.H. and Stock, S.R., Phil Trans Roy Soc (Lon) 357 (1999) 2755–2775.Google Scholar
15.Guvenilir, A., Stock, S.R., Barker, M.D. and Betz, R.A., in 4th Int Conf on Al Alloys: Their Physical and orignial Propeies, Vol. II, Sanders, T.H. Jr. and Starke, E.A. Jr., Eds. (Georgia Institute of Technology, 1994) 413–419.Google Scholar
16.Rao, K.T. Venkateswara and Ritchie, R.O., Int Mater Rev 37#4 (1992) 153–185.Google Scholar
17.Newman, J.C. Jr., NASA Langley, 1999, personal communication.Google Scholar
18.Davis, G.R. and Elliott, J.C., Nucl Instrum Meth A394 (1997) 157–162.Google Scholar
19.Morano, R., “Effect of R-ratio on Crack Closure in AI-Li 2090 T8E41, Investigated Nondestructively with x-ray Microtomography,” MS Thesis, Georgia Institute of Technology, 1998.Google Scholar
20.Breunig, T.M., Stock, S.R., Guvenilir, A., Elliott, J.C., Anderson, P. and Davis, G.R., Composites 24 (1993) 209–213.Google Scholar
21.Jung, H.Y. and Antolovich, S.D., Scr Met Mater 33 (1995) 275–281.Google Scholar
22.Stock, S.R., Int Mater Rev 44 #6 (1999) 1–24.Google Scholar