PSI - Issue 35

Sadik Sefa Acar et al. / Procedia Structural Integrity 35 (2022) 219–227 Sadik Sefa Acar et. al. / Structural Integrity Procedia 00 (2021) 000–000

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Experimental Simulation 1 Simulation 2 Simulation 3

Stress (MPa)

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Strain

Fig. 1: Experimental versus RVE stress strain response under axial loading condition for three di ff erent randomly oriented grain microstructures.

consist of grains with mean aspect ratios of (1,1,1), (0.5,1,0.5), (0.25,1,0.25) and (0.1,1,0.1), respectively where the ratio of longer dimension to the shorter dimension is gradually increased.

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Fig. 2: RVEs with di ff erent grain morphology; (a) Equiaxed, (b) Needle1, (c) Needle2, (d) Needle3

RVE represents the smallest volume element that general behavior and the mean properties of the material can be observed. So, the boundary conditions must be adjusted such that RVE can imitate the mechanical response of the material. Symmetric boundary conditions are imposed such that all surfaces of RVEs are kept straight (see e.g. Yalc¸inkaya et al. (2019)). Also, given boundary conditions maintaned the triaxiality value at 0.33 (see e.g. Yalc¸inkaya et al. (2021a)). % 10 displacement is given to RVEs as the loading condition. After RVE analyses are completed, a post-process procedure with volumetric average (i.e. homogenization) is applied to find the stress-strain responses (see e.g. Tekog˘ lu (2014)).