ESDU Fatigue - Fracture Mechanics Series

Methods and data are given for strength calculations primarily on aircraft and aerospace structures. The principles of linear elastic fracture mechanics are employed to provide data for strength analysis of cracked or flawed structures or components. The information therefore relates to damage-tolerant design.

The major body of the data consists of curves of crack propagation growth rate versus stress intensity factor range under constant amplitude fatigue loading. These data are grouped according to material, aluminium or titanium alloys or steels, and for each material the curves are grouped according to alloy type and manufacturing process. The influence of the environment is included for many materials. Where possible, mean and upper bound curves are provided.

In addition, an introduction to the principles of fracture mechanics is included with example calculations. Methods of compounding, to obtain stress intensity factors for "real life" complex geometries from simple theoretical solutions, are also treated and, for the complex case of a pin loaded lug, data for stress intensity factors are given.

A complete Section is given over to the provision of crack resistance curves for aeronautical metallic materials.