Title: New analytical methods for the prediction of fatigue crack growth under realistic loading

Authors: H.H. Van Der Linden, A.U. De Koning, C.J. Lof

Addresses: Structures and Materials Division, National Aerospace Laboratory, NLR, The Netherlands. ' Structures and Materials Division, National Aerospace Laboratory, NLR, The Netherlands. ' Structures and Materials Division, National Aerospace Laboratory, NLR, The Netherlands

Abstract: After a discussion of two aircraft design philosophies and the phenomenon of aeronautical fatigue, two new analytical methods for prediction of crack growth under realistic fatigue loading are described. The first method includes a model for prediction of fatigue crack growth in aluminium alloy sheet specimens subjected to service loading conditions. The effect of sheet thickness (plane strain to plane mess transition) and of relatively high loads on the crack opening behaviour are described by the model. The effects of load spectrum variations were predicted with high accuracy. The second method involves the application of linear elastic fracture mechanics to three dimensional crack growth predictions under constant amplitude loading. The stepwise crack growth prediction technique is summarized. Each prediction step is followed by a verification of the stress intensity along the crack front. Comparison of test results with predictions showed very good agreement.

Keywords: fatigue crack growth; aluminium alloys; centrally cracked sheet; crack opening model; spectrum variations; overload interaction; corner cracks; lugs; holes; constant amplitude loading; aircraft design.

DOI: 10.1504/IJVD.1986.061153

International Journal of Vehicle Design, 1986 Vol.7 No.3/4, pp.288 - 305

Published online: 25 May 2014 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article