Crystal viscoplasticity model for the creep-fatigue interactions in single-crystal Ni-base superalloy CMSX-8
Crystal viscoplasticity model for the creep-fatigue interactions in single-crystal Ni-base superalloy CMSX-8
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DOI：
10.1016/j.ijplas.2017.08.008
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发表时间：
2018
影响因子：
9.8
通讯作者：
E. A. E. Rodas-E.-A.-E.-Rodas-100644013;R. Neu
中科院分区：
文献类型：
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作者：
E. A. E. Rodas-E.-A.-E.-Rodas-100644013;R. Neu
提出了镍基高温合金CMSX-8蠕变-疲劳交互作用的晶体粘塑性（CVP）模型。在相关的微观结构尺度上，高温合金是由γ相和γ′强化相组成的复合材料，具有高度依赖于温度的独特变形机制。考虑各个材料相的变形差异对于预测高温合金在宽温度范围内的变形行为至关重要。在这项工作中，我们考虑到相关的变形机制，发生在两个材料相，利用两个附加应变率模型上的每个材料相的变形。该模型是能够代表单晶高温合金的蠕变疲劳相互作用的现实三维组件在Abaqus用户材料子程序（UMAT）。使用一组校准到高温合金CMSX-8的材料参数，该模型预测这种单晶高温合金的蠕变疲劳，疲劳和热机械疲劳行为。最后，进行了材料参数的敏感性研究，以探讨由于与微观结构相关的材料参数的变化对变形的影响。
A crystal viscoplasticity (CVP) model for the creep-fatigue interactions of nickel-base superalloy CMSX-8 is proposed. At the microstructure scale of relevance, the superalloys are a composite material comprised of a γ phase and a γ′ strengthening phase with unique deformation mechanisms that are highly dependent on temperature. Considering the differences in the deformation of the individual material phases is paramount to predicting the deformation behavior of superalloys at a wide range of temperatures. In this work, we account for the relevant deformation mechanisms that take place in both material phases by utilizing two additive strain rates to model the deformation on each material phase. The model is capable of representing the creep-fatigue interactions in single-crystal superalloys for realistic 3-dimensional components in an Abaqus User Material Subroutine (UMAT). Using a set of material parameters calibrated to superalloy CMSX-8, the model predicts creep-fatigue, fatigue and thermomechanical fatigue behavior of this single-crystal superalloy. Finally, a sensitivity study of the material parameters is done to explore the effect on the deformation due to changes in the material parameters relevant to the microstructure.