Micropillar Compression Deformation of Single Crystals of Fe 3Ge with the L1 2 Structure
Micropillar Compression Deformation of Single Crystals of Fe 3Ge with the L1 2 Structure
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L1 2 结构Fe 3Ge 单晶的微柱压缩变形
DOI：
10.2139/ssrn.3762209
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发表时间：
2021
期刊：
影响因子：
--
通讯作者：
H. Inui
中科院分区：
文献类型：
--
作者：
Zhenghao Chen;H. Inui
本文用微柱压缩实验研究了具有L12结构的Fe_3Ge单晶在室温下的塑性变形行为与晶体取向的关系。除了（010）上的滑移外，在Fe_3Ge中还首次观察到（111）上的滑移。通过将尺寸相关强度变化外推至“体积”尺寸，估算出（111）[10 <$1]滑移的CRSS（临界分解剪切应力）约为240 MPa，几乎是类似估算的（010）[101]滑移（约40 MPa）的6倍。B=[10 1]的超晶格位错的解离方案被证实是AP B（反相边界）型的（010）和（111），与之前的预测相比，由于预期的AP B不稳定性的超晶格本征堆垛层错（SISF）方案（111）。当在（010）上滑动时，超晶格位错没有任何优先方向来排列（表示在室温下的低摩擦应力），当在（111）上滑动时，观察到超晶格位错沿着它们的螺旋取向排列。这被证明是由于热激活的交叉滑移形成Kear-Wilsdorf锁，表明在许多其他L12化合物如Ni 3Al中观察到的屈服应力异常的发生。根据实验结果（（111）和（010）上的APB能和（111）和（010）上滑移的CRSS值），讨论了Fe_3Ge中可能出现的一些重要变形特征（如SISF偶解离的缺失和屈服应力异常的出现）。
The plastic deformation behavior of single crystals of Fe3Ge with the L12 structure has been investigated at room temperature as a function of crystal orientation by micropillar compression tests. In addition to slip on (010), slip on (111) is observed to occur in Fe3Ge for the first time. The CRSS (critical resolved shear stress) for (111)[10‾1] slip, estimated by extrapolating the size-dependent strength variation to the ‘bulk’ size, is ~240 MPa, which is almost 6 times that (~40 MPa) for (010)[101] slip similarly estimated. The dissociation scheme for the superlattice dislocation with b=[10‾1] is confirmed to be of the APB (anti-phase boundary)-type both on (010) and on (111), in contrast to the previous prediction for the SISF (superlattice intrinsic stacking fault) scheme on (111) because of the expected APB instability. While superlattice dislocations do not have any preferential directions to align when gliding on (010) (indicative of low frictional stress at room temperature), the alignment of superlattice dislocations along their screw orientation is observed when gliding on (111). This is proved to be due to thermally-activated cross-slip to form Kear-Wilsdorf locks, indicative of the occurrence of yield stress anomaly that is observed in many other L12 compounds such as Ni3Al. Some important deformation characteristics expected to occur in Fe3Ge (such as the absence of SISF-couple dissociation and the occurrence of yield stress anomaly) will be discussed in the light of the experimental results obtained (APB energies on (111) and (010) and CRSS values for slip on (111) and (010)).
影响因子：
6
作者：
Chen, Zhenghao M. T.;Okamoto, Norihiko L.;Inui, Haruyuki
通讯作者：
Inui, Haruyuki