Modeling of intragranular misorientation and grain fragmentation in polycrystalline materials using the viscoplastic self-consistent formulation
Modeling of intragranular misorientation and grain fragmentation in polycrystalline materials using the viscoplastic self-consistent formulation
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DOI：
10.1016/j.ijplas.2018.06.004
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发表时间：
2018-10
影响因子：
9.8
通讯作者：
M. Zecevic;R. Lebensohn;R. Mccabe;M. Knezevic
中科院分区：
文献类型：
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作者：
M. Zecevic;R. Lebensohn;R. Mccabe;M. Knezevic
利用多晶聚集体晶粒内应力场二阶矩的已知算法表达式，采用平均场粘塑性自洽（VPSC）方法，计算了晶粒内晶格旋转速率的平均涨落和相应的平均晶内取向差分布将该公式推广到考虑晶内取向差对应力和转速波动影响的耦合问题。反过来，这些耦合的表达式被用来制定和实施的颗粒破碎（GF）模型VPSC。包括面心立方多晶体的拉伸和平面应变压缩的案例研究被用来说明新模型的能力。GF-VPSC预测的晶内取向差分布和织构演化的实验和全场数值模拟进行了比较，表现出良好的一致性。特别是，包括取向差传播的变形纹理的强度降低，从而提高了纹理预测。此外，考虑到晶内取向差作为再结晶的驱动力，新的GF-VPSC配方，使变形和再结晶过程中的微观结构演变建模，在计算效率的方式。
The recently established methodology to use known algorithmic expressions of the second moments of the stress field in the grains of a polycrystalline aggregate for calculating average fluctuations of lattice rotation rates and the associated average intragranular misorientation distributions using the mean-field viscoplastic self-consistent (VPSC) formulation is extended to solve the coupled problem of considering the effect of intragranular misorientations on stress and rotation rate fluctuations. In turn, these coupled expressions are used to formulate and implement a grain fragmentation (GF) model in VPSC. Case studies, including tension and plane-strain compression of face-centered cubic polycrystals are used to illustrate the capabilities of the new model. GF-VPSC predictions of intragranular misorientation distributions and texture evolution are compared with experiments and full-field numerical simulations, showing good agreement. In particular, the inclusion of misorientation spreads reduced the intensity of the deformed texture and thus improved the texture predictions. Moreover, considering that intragranular misorientations act as driving forces for recrystallization, the new GF-VPSC formulation is shown to enable modeling of microstructure evolution during deformation and recrystallization, in a computationally efficient manner.