ESDU Fat E.07.01 gives graphs showing the results of some 3500 constant amplitude tests on smooth machined or polished circular section specimens tested in reversed bending, as a rotating cantilever or as a rotating beam. Each graph relates to a particular material: naturally-aged Al-Cu-Mg alloys L64 and 2024, artificially-aged Al-Zn-Mg DTD 683 and 7075 and artificially-aged Al-Cu-Mg alloy L65. Most results were obtained from specimens 10 mm (0.4 in) diameter at the critical section, but a few were from specimens between 25 mm (1 in) and 45 mm (1.74 in) diameter. The specimens were either unnotched or had stress concentrations lying between 1.45 and 3; each plotted point indicates the stress concentration present.