Review of and a new approach to elastic modulus evaluation for fatigue design of metallic components

Abstract

Abstract The elastic modulus is a key parameter for the description of material properties when evaluating metallic components under service loads. In particular, when evaluating strain-controlled tests for the application of the strain-life approach, there are numerous different possibilities in standards for determining this material parameter. These can lead to different results and confront the user with a certain challenge in selecting the most suitable method. In this publication, an overview of different evaluation methods is given and a new evaluation method is presented, in which the elastic modulus is determined using the reversal points of a strain-controlled cyclic test under macroscopic linear-elastic deformation. This allows a simple and clear, widely user-independent determination of the elastic modulus. In addition, the differences between the new and the commonly used evaluation methods are shown, using the example of the aluminum alloy EN AW-7075, and their influence on the strain-life curve, the PSWT and PJ damage parameter curves, and the cyclic stress-strain curve by Ramberg-Osgood are investigated.