Abstract
The methodology to predict the increase in crack growth resistance due to crack deflection and branching is described. These procedures are discussed with respect to an Al-Li alloy 2090 sheet in T6 condition, the R-curve tests on which revealed that the crack path in L-T orientation was deflected and branched while it remained nominally straight in T-L orientation. The resistance to slow stable crack extension in L-T orientation was found to be significantly higher as compared to that in T-L orientation. Such behaviour is rationalized in terms of crack deflection and branching. The observed variation in the crack path morphology and the resulting R-curves in L-T and T-L orientations can be understood in terms of the microstructural features of the alloy.
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References
T.H. Sanders and E.A. Starke (eds.), Aluminium-Lithium Alloys, Proceedings 1st International Aluminium-Lithium Conference, The Metallurgical Society of AIME, Warrendale, PA (1981).
W.E. Quist and G.H. Narayanan, in Aluminium Alloys-Contemporary Research and Applications, Treatise on Material Science Technology, Vol. 31, A.K. Vasudevan and R.D. Doherty (eds.), Academic Press Inc., San Diego, CA (1989) 219–254.
R. Grimes, A.J. Cornish, W.S. Miller and M.A. Reynolds, Metals and Materials 1 (1985) 357–363.
T.H. Sanders and E.A. Starke, Acta Metallurgica 30 (1982) 927–939.
P.J. Gregson and H.M. Flower, Acta Metallurgica 33 (1985) 527–537.
K.V. Jata and E.A. Starke, Metallurgical Transactions 17A (1986) 1011–1026.
A.K. Vasudevan and S. Suresh, Materials Science and Engineering 72 (1985) 37–49.
T.H. Sanders, Factors Influencing Fracture Toughness and Other Properties, Final Report Naval Air Development Centre Contract No. N62269-76-C-0271 (1979).
S. Suresh, Metallurgical Transactions 16A (1985) 249–260.
K.T. Venkateswara Rao, R.J. Bucci, K.V. Jata and R.O. Ritchie, Materials Science and Engineering A141 (1990) 39–48.
K.T. Venkateswara Rao and R.O. Ritchie, Materials Science and Technology 5 (1989) 896–907.
K.T. Venkateswara Rao and R.O. Ritchie, Materials Science and Technology 100 (1988) 23–30.
K.T. Venkateswara Rao and R.O. Ritchie, Acta Metallurgica 36 (1988) 2849–2862.
G.R. Yoder, P.S. Pao, M.A. Imam and L.A. Cooley, Scripta Metallurgica 23 (1989) 1455–1458.
C.S. Carter, Engineering Fracture Mechanics 3 (1971) 1–13.
M.O. Speidel, Branching of Stress Corrosion Cracks in Aluminim Alloys, NATO Conference, Ericeira (1971).
S. Suresh and A.K. Vasudevan, Materials Science and Engineering 79 (1986) 183–190.
S. Suresh, A.K. Vasudevan, M. Tosten and P.R. Howell, Acta Metallurgica 35 (1987) 25–46.
S.V. Kamat and N. Eswara Prasad, Scripta Metallurgica et Materialia 24 (1990) 1907–1912.
N. Eswara Prasad, S.V. Kamat and G. Malakondaiah, in Aluminium-Strategies for Nineties and Beyond, Proceedings International Conference on Aluminium, Incal 91, Vol. 2, The Aluminium Association of India, Bangalore, India (1991) 613–620.
ASTM Annual Book of Standards, American Society of Testing and Materials, E-561, Vol. 03.01 (1989) 570–582.
P.S. Theocaris, Journal of the Mechanics and Physics of Solids 20 (1972) 265–279.
H. Kitagawa, R. Yuuki and T. Ohira, Engineering Fracture Mechanics 7 (1975) 515–529.
B.A. Bilby and G.E. Cardew, International Journal of Fracture 11 (1975) 708–712.
B. Cotterell and J.R. Rice, International Journal of Fracture 16 (1980) 155–169.
S. Suresh, Metallurgical Transactions 14A (1983) 2375–2385.
K.K. Lo, Journal of Applied Mechanics 45 (1978) 797–802.
S. Suresh and C.F. Shih, International Journal of Fracture 30 (1986) 231–259.
D. Broek, in Elementary Engineering Fracture Mechanics, Martinus Nijhoff Publishers, Dortrecht (1976) 374.
N. Eswara Prasad and S.V. Kamat, unpublished research.
E.A. Starke and F.S. Lin, Metallurgical Transactions 13A (1982) 2259–2269.
T.S. Srivatsan, T.A. Place and T.S. Sudarshan, in Advances in Fracture Research, Proceedings 7th International Conference on Fracture, Vol. 4, K. Salama, K. Ravi-Chandar, D.M.R. Taplin and P. Rama Rao (eds.), Pergamon Press, N.Y. (1989) 2611–2621.
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Prasad, N.E., Kamat, S.V. & Malakondaiah, G. Effect of crack deflection and branching on the R-curve behaviour of an Al-Li alloy 2090 sheet. Int J Fract 61, 55–69 (1993). https://doi.org/10.1007/BF00032339
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DOI: https://doi.org/10.1007/BF00032339