Stulen, Foster B.
Chief Structures Engineer, Curtiss-Wright Corp., Propeller Division, Caldwell, N. J.
Pages: 22 Published: Jan 1952
Usually conventional fatigue tests are not designed to evaluate the character and dispersion of the fatigue life and endurance limit of a material, and as a result little is known about these important characteristics of materials. Several methods are proposed in this paper for the determination of these characteristics, and the results of tests utilizing these techniques as well as methods of graphically representing the data are given.
The elementary theory of extreme values as related to the size effect is given in this paper. Explanations of the understressing effect and of the variation in notch sensitivity between different materials are proposed.
Tests have also been conducted which show that the material near the surfaces and edges of the specimens appears to have lower endurance limits than the material in the interior of the specimens. This is in agreement with observations recently made by several other investigators.
Paper ID: STP43997S