The molecular dynamics simulation has been performed to study the effects of temperature on interdiffusion of Ni–Zr system. The simulated results indicate that the thickness of Ni/Zr diffusion layer increased with increasing diffusion time, and interdiffusion results in disordered or amorphization in the diffusion zone. During the diffusion process, Ni atoms diffuse crossing the interface more easily and deeply into Zr side than Zr atoms into Ni side. The activation energies of Ni and Zr are 1.25 and 1.28 eV for Ni(100)//Zr(0001) interface, 1.33 and 1.42 eV for Ni(110)//Zr(0001) interface at the temperature range of 950–1100 K, respectively. The microscopic diffusion mechanisms for Ni atoms in Zr lattice have been studied, and the results show that the most possible diffusion mechanism is the interstitial hopping mechanism, while for Zr diffusing in Ni, the vacancy diffusion mechanism is favored. The interdiffusion for case of Ni(110)//Zr(0001) interface is more easy than that of Ni(100)//Zr(0001) interface due to the lower surface energy for the former. In the diffusion zone of Ni–Zr, some typical clusters have been identified, which are similar to those extracted from the Ni–Zr intermetallic compounds, and which are generally consistent with the experimental observations in diffusion couples.

中文翻译：

---

Ni-Zr界面扩散的分子动力学模拟

已经进行了分子动力学模拟以研究温度对Ni-Zr体系相互扩散的影响。模拟结果表明，Ni/Zr扩散层厚度随着扩散时间的增加而增加，相互扩散导致扩散区无序或非晶化。在扩散过程中，Ni原子比Zr原子更容易和更深地穿过界面扩散到Zr侧。在 950-1100 K 温度范围内，Ni 和 Zr 的活化能为 Ni(100)//Zr(0001) 界面的活化能分别为 1.25 和 1.28 eV，Ni(110)//Zr(0001) 界面的活化能分别为 1.33 和 1.42 eV ， 分别。研究了Zr晶格中Ni原子的微观扩散机制，结果表明最可能的扩散机制是间隙跳跃机制，而对于 Zr 在 Ni 中的扩散，空位扩散机制是有利的。Ni(110)//Zr(0001)界面比Ni(100)//Zr(0001)界面更容易相互扩散，因为前者的表面能较低。在 Ni-Zr 的扩散区，已经确定了一些典型的簇，这些簇与从 Ni-Zr 金属间化合物中提取的簇相似，与扩散偶中的实验观察结果基本一致。