A Computational Methodology for Fatigue Life Prediction Under Multiaxial Non-Proportional Loading 2001-01-0837
A methodology for predicting the fatigue initiation life in metals experiencing multiaxial non-proportional loading is presented. The methodology utilizes nonlinear finite-element analysis to determine the stress distribution of the loaded component. This distribution is used in conjunction with a physically based damage law to determine the cycles to failure. The damage law is based on the fatigue prediction method introduced by Dang Van [1], and further developed by Papadopoulos [2] and Morel [3]. The fatigue damage initiation is treated as the persistent crystalline slip phenomenon taking place on the order of a grain or few grains. The damage variable is chosen to be the accumulated plastic strain at this scale. The initiation life is determined when the damage variable reaches a critical value. The developed methodology is applicable to both in-phase and out-of-phase loading, without any empirical adjustment parameter. In order to validate the methodology, the predictions are compared with the experimental results on tension-torsion of thin walled steel tubes by Fatemi and Stephens [4]. Conservative predictions within a factor of 4 for proportional loading and slightly over a factor of 4 for non-proportional loading are obtained. Thus, this methodology shows promise as a practical tool that could be used in durability predictions of components experiencing complex loading conditions
Citation: Mohan, R., "A Computational Methodology for Fatigue Life Prediction Under Multiaxial Non-Proportional Loading," SAE Technical Paper 2001-01-0837, 2001, https://doi.org/10.4271/2001-01-0837. Download Citation
Author(s):
Raj Mohan
Affiliated:
Rouge Steel Company
Pages: 16
Event:
SAE 2001 World Congress
ISSN:
0148-7191
e-ISSN:
2688-3627
Also in:
SAE 2001 Transactions Journal of Materials & Manufacturing-V110-5
Related Topics:
Finite element analysis
Fatigue
Metals
Steel
Slip
Logistics
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