The use of structural metals in extreme environments relies both on the characterization of the mechanical response and microstructure changes in service and on modeling predictions. Data scarcity creates a need for predictive constitutive models that can be used in regimes outside calibration domains. While crystal plasticity models can be applied to non-monotonic loads and complex environments, their computational cost typically prohibits use at the level of an engineering structure. As an alternative, the present study introduces a surrogate constitutive model derived from crystal-plasticity predictions of the mechanical response of HT9 subjected to irradiation, stresses and temperatures. The surrogate law is then tested in the cases of uniaxial straining, stress cycling, thermal cycling and thermal ramping. Finally, using this constitutive relationship, finite element simulations of a pressurized tube subjected to a stress and thermal transients are performed and analyzed.

中文翻译：

---

钢中粘塑性的替代建模：在 HT-9 包层中应用于热、辐照蠕变和瞬态载荷

在极端环境中使用结构金属既依赖于机械响应和微观结构变化的表征，也依赖于建模预测。数据稀缺产生了对可用于校准域之外的制度的预测本构模型的需求。虽然晶体塑性模型可以应用于非单调载荷和复杂环境，但它们的计算成本通常禁止在工程结构级别使用。作为替代方案，本研究引入了一种替代本构模型，该模型源自对 HT9 在辐照、应力和温度下的机械响应的晶体塑性预测。然后在单轴应变、应力循环、热循环和热斜坡的情况下测试替代定律。最后，