Improved fatigue damage accumulation analysis based on material memory property

Abstract

Purpose

For the difference of the change law of material memory performance and the influence of damage state on memory performance, this paper aims to establish a general model of fatigue damage accumulation based on dynamic residual S–N curve and material memory characteristics.

Design/methodology/approach

This paper introduces the material memory characteristics, combined with the residual S–N curve method, and uses the exponential decay function of the load cycle to construct the material memory performance function. While considering the damage state, the loading order can be fully considered. The parameter d in the function not only represents the variation of the material's memory property, but also considers the influence of the damage state.

Findings

According to the test data of welding joints of common materials, alloy materials and other materials, the validity and feasibility of the fatigue cumulative damage model constructed were verified. The numerical results show that under the grading load, the fatigue cumulative damage model can be used to predict the fatigue life of welded structures and has high prediction accuracy and more approximate to the actual experiment results. It can be directly applied to the fatigue life prediction and design of actual engineering welded structures.

Originality/value

The model not only considers the effect of damage state and loading order on damage accumulation, but also contains only one material parameter, which is easy to obtain. The prediction accuracy and engineering practicability of fatigue were significantly improved.

Citation

Xu, X., Xue, Q., Ku, Z., Li, H. and Hu, J. (2021), "Improved fatigue damage accumulation analysis based on material memory property", International Journal of Structural Integrity, Vol. 12 No. 2, pp. 214-225. https://doi.org/10.1108/IJSI-01-2020-0002