PSI - Issue 71

Manan Ghosh et al. / Procedia Structural Integrity 71 (2025) 445–452

451

Fig. 3: (a)Evolution of variables 0 , 3 3 and (b) 0 with cycles obtained from the multi-time scale method Fig. 4 shows the heterogeneous distribution of 33 along two different material lines, which are (x = 0.5, y, z = 0.5) and (x, y = 0.5, z = 0.5) in the microstructure at τ = 1 sec in the 10,000 th and 100,000 th cycles. It can be observed from the figures that the stress evolves with time. Also, the maximum and minimum increases and decreases respectively, which can cause fatigue crack nucleation in the microstructure

Fig. 4: Comparison of σ 33 along lines (a) (X = 0.5, Y, Z = 0.5) (b) (X, Y = 0.5, Z = 0.5) line at τ = 1 sec in 10,000

th and 100,000 th cycles

5. Summary This paper presents a Haar scaling-based multi-time scale algorithm for accelerating cyclic CPFEM simulations, crucial for predicting HCF failure in polycrystalline materials. The method effectively retains high-frequency responses through the basis functions and converts the low-frequency material responses into a monotonic cycle scale problem without requiring scale separation or periodicity-based homogenization. This method is stable, as it performs coarse scale integration implicitly. A statistically equivalent microstructure with BCC crystallography is used to evaluate the accuracy and computational efficiency of the multi-time scale method compared to single time scale method. The cycle scale solutions show excellent agreement with single time scale solutions while offering significant computational efficiency. Acknowledgements The authors express their gratitude to Hydro-Quebec, Canada, for funding this work through the strategic project Modelisation Micromecanique des Aciers (MoMA) J-8587.

References

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