A micromechanical fatigue model with damage morphology
| Autor: | Eli Altus, Elisha Rejovitzky |
|---|---|
| Rok vydání: | 2011 |
| Předmět: |
Coalescence (physics)
Materials science Differential equation business.industry Mechanical Engineering Failure strain Structural engineering Mechanics Shape of the distribution Fatigue limit Strength of materials Industrial and Manufacturing Engineering Exact solutions in general relativity Mechanics of Materials Modeling and Simulation Fatigue loading General Materials Science business |
| Zdroj: | International Journal of Fatigue. 33:1235-1243 |
| ISSN: | 0142-1123 |
| DOI: | 10.1016/j.ijfatigue.2011.03.015 |
| Popis: | A stochastic two-parameter Micromechanical Fatigue Model (MFM), which considers morphological aspects of microcrack coalescence and arrest, is proposed. The material is modeled as an ensemble of elements with a stochastic failure strain distribution. By using set theory tools, equilibrium and material strength partitioning, an analytical fatigue life relation is obtained. The cycle-by-cycle damage evolution is transformed into a continuous form, leading to a non-linear separable differential equation. An exact solution of this equation yields the familiar stress-life power-law ( σ = AN b ) and endurance limit. These are directly related to two characteristic micromechanical parameters of material heterogeneity: the strength distribution shape factor of the ensemble and the microcrack arrest probability. The model proposes a new generic relation between the damage evolution function and the S–N power-law, which is validated by recent experiments for three different steels studied elsewhere. The damage evolution morphology includes the full microcrack size distribution. Good prediction capabilities are obtained for high-to-low two-level fatigue loading based on single-level data only. |
| Databáze: | OpenAIRE |
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