Abstract
The strain concentration factors were determined for aluminum alloy 7085 in the T7651 temper using multi-hole structural coupon specimens. Samples of the alloy were evaluated for both the 6.25 mm (0.25 in.) thick and 10 mm (0.4 in.) thick specimens having widths of 50 mm (2 in.) and 100 mm (4 in.), respectively. For the case of the specimens that were 50 mm in width, the mechanical tests were conducted for both the open-hole and filled-hole conditions and the corresponding strain concentration value was determined. For the filled-hole test specimens, threaded fasteners having collars were used. In order to provide for some interference, the fasteners had a shank diameter that was slightly larger than the nominal hole size. The strain concentration values were evaluated at both the failure strain (εf) and the strain at maximum load (εmax). The average strain concentration value was then used to predict the results for the stack-up tests.
Similar content being viewed by others
References
R.T. Shuey, F. Barlat, M.E. Karabin, and D.J. Chakrabarti, Experimental and Analytical Investigations on Plane Strain Toughness for 7085 Aluminum Alloy, Metall. Mater. Trans. A, 2009, 40, p 365–376
G.H. Bray, “Comparison of Open Hole and Joint S/N Fatigue Test Results for Standard and High Purity 7055-T7751 Plate,” ATC Report 01A56501, Pittsburgh, PA, 1998
M. Mohaghegh, Tension Analysis of Stiffened Aircraft Structures, AIAA-85-0795-CT, 26th Annual Joint Conference of AIAA/ASME/ASCE/AHS Structures, Structural Dynamics and Materials Conference, Orlando, FL, 1985
C. Giummara and H.R. Zonker, Improving the Fatigue Response of Aerospace Structural Joints, ICAF 2005 Proceedings, Hamburg, Germany, 2005
D.J. Chakrabarti, J. Liu, R.R. Sawtell, and G.B. Venema, Proceedings of ICAA9 (North Melbourne), Institute of Materials Engineering Australasia Ltd., 2004, p 969–974
D.F. Lam, “Strain Concentration and Tension Dominated Stiffened Aerospace Structures,” Master of Science Thesis, The University of Akron, Akron, OH, May 2006
C.C. Menzemer, “Strain Concentration and Tension Dominated Stiffened Aerospace Structures,” Final Technical Report to Aluminum Company of America, March 2006
T.S. Srivatsan, D. Lanning, Jr., and K. Soni, Cyclic Strain Resistance and Fracture Behavior of High Strength Aluminum Alloy, J. Mater. Sci., 1993, 28, p 3205–3213
T.S. Srivatsan, Microstructure, Tensile Properties and Fracture Behavior of Aluminum Alloy 7150, J. Mater. Sci., 1992, 27, p 4772–4781
D. Hoeppner, S. Adibnazari, and M.W. Moesser, “Literature Review and Preliminary Studies of Fretting and Fretting Fatigue Including Special Applications to Aircraft Joints,” Report DOT/FAA/CT-93/2
E.R. Speakman, Advance Fastener Technology for Composite and Metallic Joints, Fatigue in Mechanically Fastened Composite and Metallic Joints, ASTM STP 927, J.M. Potter, Ed. (Philadelphia, PA), American Society for Testing and Materials, 1986, p 5–38
T.S. Srivatsan and V.K. Vasudevan, The High Strain Cyclic Fatigue and Fracture Behavior of Two Al-Cu-Mg Alloys, Met. Mater. Processes, 1994, 6(2), p 97–106
Acknowledgments
The material used in this exhaustive research study was provided by ALCOA (Aluminum Company of America). Sincere thanks and appreciation is extended to the research personnel at ATC (ALCOA Technical Center) for providing financial support as well as the relevant data required for this research study. Thanks are also extended to the University of Akron for providing tuition support to the graduate student. Finally, the authors extend overwhelming thanks and appreciation to the two unknown reviewers whose comments, corrections and suggestions have helped strengthen the revised manuscript.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Menzemer, C.C., Lam, D.F. & Srivatsan, T.S. An Investigation of Strain Concentration in High-Strength Al-Zn-Mg-Cu Alloy 7085 Subjected to Tensile Deformation. J. of Materi Eng and Perform 19, 705–713 (2010). https://doi.org/10.1007/s11665-009-9524-5
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11665-009-9524-5