Anisotropic yielding stress of 2198 Al–Li alloy sheet and mechanisms
Anisotropic yielding stress of 2198 Al–Li alloy sheet and mechanisms
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2198铝锂合金板材的各向异性屈服应力及机理
DOI：
10.1016/j.msea.2019.138572
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发表时间：
2020-01
期刊：
影响因子：
--
通讯作者：
Zhang Shi-Hong
中科院分区：
文献类型：
--
作者：
Zhao Tian-Zhang;Jin Long;Xu Yong;Zhang Shi-Hong
通过轧制方向（RD）、45°和横向（TD）3个方向的单轴拉伸试验，系统研究了2198铝锂合金板材在新淬火、自然时效和人工时效3种热处理状态下的各向异性力学行为。结果表明，淬火和自然时效后屈服应力的各向异性相似，这主要是由于相同的晶体织构所致。自然时效过程中产生的δ′相对各向异性无影响，但均匀地提高了强度。而2198 Al-Li合金经人工时效后，由于T1在{111}面的四种不同变体上分布不均匀，表现出不同的屈服应力各向异性。这主要是由于预变形过程中位错滑移的不均匀激活引起的，粘塑性自洽模型的计算结果证实了这一点。提出了一个新的因子T来考虑T1对各向异性屈服应力的贡献。此外，建立了一个新的解析模型，预测了不同热处理工艺和不同预变形量下2198铝锂合金板材的各向异性屈服应力，与实验结果吻合较好。
The anisotropic mechanical behaviors of 2198 Al–Li alloy sheet under different heat treatments, including new quenching, natural ageing and artificial ageing, were systematically assessed via uniaxial tensile tests in three different directions: rolling direction (RD), 45°and transverse direction (TD). It's found that the anisotropy of yielding stress after quenching and natural ageing is similar, mainly owing to the same crystallographic texture. The δ′ participate generated during natural ageing has no influence on the anisotropy but increases the strength homogeneously. By contrast, 2198 Al–Li alloy after artificial ageing exhibits a different anisotropy of the yielding stress due to the inhomogeneous distribution of T1participate on four different variants of {111} plane. It is mainly caused by the inhomogeneous activation of dislocation glide during the pre-deformation, which has been verified by the calculation result via the visco-plastic self-consistent model. A new factor, T, has been proposed to consider the contribution of T1on the anisotropic yielding stress. In addition, a new analytical model has been established to predict the anisotropic yielding stress of 2198 Al–Li alloy sheet under different heat treatments and with different pre-deformation, which agrees well with the experimental results.
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影响因子：
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A. Zhu;E. Starke
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4.2
作者：
D. Steglich;H. Wafai;W. Brocks
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D. Steglich;H. Wafai;W. Brocks
DOI：
10.1007/s11661-999-0277-4
发表时间：
1999-05
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Metallurgical and Materials Transactions A
影响因子：
--
作者：
M. Lyttle;J. Wert
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M. Lyttle;J. Wert
DOI：
10.1179/030634572790445975
发表时间：
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期刊：
Metal Science Journal
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--
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B. Noble;G. Thompson
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B. Noble;G. Thompson
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