A number of studies have directly compared measurements of polycrystals’ deformation to the solution of a crystal plasticity model of the same polycrystal. An accurate representation of the full 3D microstructure and the boundary conditions has been shown to be important to obtain a good correspondence between the behaviour of the real and the simulated polycrystal. However, much less is known about the relationship between the global and the local solutions of crystal plasticity models and the influence of material parameters on the local response of the polycrystal. To address these questions, uncertainty quantification and sensitivity analysis are performed on finite element models of oligocrystals with a crystal plasticity material model. The results show significant variations in the simulated stress and strain fields due to variations in the material parameters. Sensitivity analysis is used to quantify the contribution of crystal orientation, latent hardening and other material model parameters to the variability of the crystal plasticity finite element model solution. The uncertainty in the stress and strain fields and their sensitivities vary between the oligocrystals, but nevertheless, some distinct trends can be identified. The most prominent trend is that, in general, the solution is most sensitive to the variations of the latent hardening description and the crystallographic orientations of the constituent crystals.

中文翻译：

---

晶体塑性有限元模型中材料参数的不确定度量化及灵敏度分析

许多研究直接将多晶变形的测量与同一多晶的晶体塑性模型的解进行了比较。已证明完整 3D 微观结构和边界条件的准确表示对于获得真实多晶和模拟多晶行为之间的良好对应非常重要。然而，关于晶体塑性模型的全局和局部解之间的关系以及材料参数对多晶局部响应的影响知之甚少。为了解决这些问题，我们对具有晶体塑性材料模型的寡晶有限元模型进行了不确定性量化和灵敏度分析。结果表明，由于材料参数的变化，模拟的应力和应变场发生了显着变化。灵敏度分析用于量化晶体取向、潜在硬化和其他材料模型参数对晶体塑性有限元模型解的可变性的贡献。应力和应变场的不确定性及其敏感性在寡晶之间有所不同，但仍然可以确定一些不同的趋势。最突出的趋势是，一般来说，溶液对潜在硬化描述和组成晶体的晶体取向的变化最敏感。潜在硬化和其他材料模型参数对晶体塑性有限元模型解的可变性。应力和应变场的不确定性及其敏感性在寡晶之间有所不同，但仍然可以确定一些不同的趋势。最突出的趋势是，一般来说，溶液对潜在硬化描述和组成晶体的晶体取向的变化最敏感。潜在硬化和其他材料模型参数对晶体塑性有限元模型解的可变性。应力和应变场的不确定性及其敏感性在寡晶之间有所不同，但仍然可以确定一些不同的趋势。最突出的趋势是，一般来说，溶液对潜在硬化描述和组成晶体的晶体取向的变化最敏感。