Modeling large-strain deformation behavior and neighborhood effects during hot working of a coarse-grain nickel-base superalloy
Modeling large-strain deformation behavior and neighborhood effects during hot working of a coarse-grain nickel-base superalloy
复制标题
模拟粗晶镍基高温合金热加工过程中的大应变变形行为和邻域效应
DOI：
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发表时间：
2011
期刊：
影响因子：
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通讯作者：
S. Semiatin
中科院分区：
文献类型：
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作者：
T. Turner;S. Semiatin
等温，单轴压缩试验和相应的数值模拟进行了Waspaloy锭试样，以量化变形的不均匀性在热加工的粗，柱状晶粒材料。这被用作近似铸锭材料中的变形处理的手段。在压缩测试之前和之后进行电子背散射衍射（EBSD）测量以量化微观结构演变。晶体塑性有限元法模型，其中初始微观结构实例化使用未变形材料的EBSD扫描，被用来模拟变形。良好的协议之间的观察和模拟预测的试样轮廓和晶粒内的取向差。模拟结果还表明，晶粒邻域似乎是一个主要因素控制变形的不均匀性在晶粒尺度上。一个给定的晶粒的模拟变形的显着差异，注意到其邻居的取向的各种安排。特别是，一个给定的晶粒的第一和第二最近的邻居有最显着的非均质变形行为的影响。
Isothermal, uniaxial compression tests and accompanying numerical simulations were conducted on Waspaloy-ingot specimens to quantify deformation heterogeneity during hot working of coarse, columnar-grain materials. This was used as a means to approximate deformation processing in ingot materials. Electron-backscatter-diffraction (EBSD) measurements were made before and after compression testing to quantify microstructure evolution. A crystal-plasticity finite-element-method model, in which the starting microstructure was instantiated using EBSD scans of the undeformed material, was used to simulate the deformation. Good agreement was found between observations and simulation predictions of specimen profiles and intra-grain misorientations. The simulation results also revealed that the grain neighborhood appeared to be a principal factor controlling the heterogeneity of deformation at the grain scale. Significant differences in the simulated deformation of a given grain were noted for various arrangements of the orientations of its neighbors. In particular, the first- and second-nearest neighbors of a given grain have the most significant effect on heterogeneous deformation behavior.