Time evolution of the structure function of quenched Al-Zn and Al-Zn-Mg alloys.
Time evolution of the structure function of quenched Al-Zn and Al-Zn-Mg alloys.
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淬火 Al-Zn 和 Al-Zn-Mg 合金结构函数的时间演化。
DOI：
10.1103/physrevb.31.1278
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发表时间：
1985
期刊：
影响因子：
--
通讯作者：
Takayoshi Takeda
中科院分区：
文献类型：
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作者：
S. Komura;K. Osamura;Hironobu Fujii;Takayoshi Takeda
Al-6.8 at分解。% Zn和Al-10 at。% Zn的二元合金和三元合金，进一步添加0.1 at。用小角中子散射法研究了% Mg在不同温度（18℃、40℃和80℃）下淬火进入混相隙并时效的过程。根据Furukawa提出的结构函数S （k, t）的时间演化理论，考虑到S （k, t）的缩放特性、星团的迁移率M (t)和星团气体的扩散率dt (k, t)，分析了不同时效时间t下散射矢量k的散射截面dΣ (k, t)/dΩ。结果表明，对于不同时效温度下的各种样品，具有特征簇大小为R (t)∝t1的简单动态标度律S (k, t)∝R (t) 3s n （kR (t)）和通用标度函数S n (x)∝x2 /(γ/2+ x2 + γ)的时效时间范围很广。从分析中我们可以提取M (t)和dt （k, t）的时间演化，这应该决定了S （k, t）的演化，这样我们就可以数值计算dΣ (k, t)/dΩ的时间演化，与相应的观测量很好地吻合。
The decomposition of Al–6.8 at.% Zn and Al–10 at.% Zn binary alloys and ternary alloys with the further addition of 0.1 at.% Mg, quenched into the miscibility gap and aged at different temperatures (18, 40, and 80 C), has been studied by small-angle neutron scattering. The scattering cross section dΣ (k, t)/dΩ as a function of scattering vector k at different aging times t has been analyzed in terms of time-evolution theory of the structure function S (k, t), proposed by Furukawa, taking into account the scaling properties of S (k, t), the mobility M (t) of the clusters, and the diffusivity D T (k, t) of a cluster gas. The results show that a simple dynamical scaling law S (k, t)∝ R (t) 3 S̃ (kR (t)) with a characteristic cluster size R (t)∝ t a and a universal scaling function S̃ (x)∝ x 2/(γ/2+ x 2+ γ) holds for a wide range of aging times for various samples with different aging temperatures. From the analysis we could extract the time evolution of M (t) and D T (k, t), which should determine the evolution of S (k, t), and thus we were able to calculate numerically the time evolution of dΣ (k, t)/dΩ in good agreement with corresponding observed quantities.