Analysis of the Effect of Load Ratio on Fatigue Crack Growth
In this paper, fatigue test and numerical simulation are carried out for Q345 weld joint under constant amplitude loading at different R-ratio using the compact tension samples with 3.8mm thickness. The result indicates that fatigue crack growth rates in the base metal is not sensitive to R-ratio, but the fatigue crack growth rates increases in the weld zone with R-ratio increasing. The effect of R-ratio on fatigue crack growth is analyzed based on J-S cycle plasticity model and Jiang’s multiaxial fatigue criterion. The finite element method (FEM) is used for the stress-strain analysis with the implementation of an accurate J-S cyclic plasticity model. With the detailed stresses and strains, fatigue damage assessment is made using a Jiang’s multiaxial fatigue criterion.
Qi Luo and Yuanzhi Wang
Y. Xiong "Analysis of the Effect of Load Ratio on Fatigue Crack Growth", Advanced Materials Research, Vols. 181-182, pp. 330-336, 2011