Uranium (U) is alloyed with molybdenum (Mo) or zirconium (Zr) in order to stabilize the high-temperature body-centered cubic $\gamma$ phase of uranium for use in nuclear reactors. Although these two alloy systems possess different mechanical, chemical and thermodynamic properties, they exhibit a similarity in that there exists a variable degree of phase decomposition from the cubic $\gamma$ phase of uranium to the orthorhombic $\alpha$ phase of uranium, depending on both the Mo/Zr content and fabrication conditions. These two phases of uranium are believed to exhibit distinct swelling and radiation damage behavior. Understanding the differences in behavior under irradiation between the $\alpha$ and $\gamma$ phases can provide valuable information to guide the manufacturing process of U alloys and can inform multi-physics, continuum-level fuel performance codes. The threshold displacement energy (TDE) is the minimum amount of kinetic energy required to displace an atom from its lattice site. It is critically important to determine an accurate value of the TDE in order to calculate the total number of displacements due to a given irradiation condition, and thus to understand the materials response to irradiation. In this study, molecular dynamics simulations have been performed to calculate the threshold displacement energy for both the $\alpha$ and $\gamma$ phases of uranium as a function of temperature. This study utilizes three different interatomic potentials that have been previously developed: U MEAM, U-Zr MEAM and U-Mo ADP. The threshold displacement energy in $\gamma U$ at 800 K is 73.2 eV, 47.1 eV and 35.6 eV for the U MEAM, U-Zr MEAM and U-Mo ADP potentials. respectively. The threshold displacement energy for $\alpha$U at 600 K is 66.3 eV for the U-Mo ADP.

铀（U）与钼（Mo）或锆（Zr）合金化以稳定高温体心立方 $\gamma$用于核反应堆的铀阶段。尽管这两种合金系统具有不同的机械，化学和热力学性质，但它们表现出相似之处，因为立方相中存在不同程度的相分解。$\gamma$ 铀到正交晶相 $\alpha$铀的相，取决于Mo / Zr含量和制造条件。据信这两个阶段的铀表现出明显的溶胀和辐射破坏行为。了解受照者之间在照射下的行为差异$\alpha$ 和 $\gamma$阶段可以提供有价值的信息，以指导U合金的制造过程，并可以告知多物理场，连续性级别的燃料性能规范。阈值位移能（TDE）是将原子从其晶格位置位移所需的最小动能。至关重要的是，确定TDE的准确值，以便计算由于给定辐照条件而产生的位移总数，从而了解材料对辐照的响应。在这项研究中，已经进行了分子动力学模拟以计算两个分子的阈值位移能。$\alpha$ 和 $\gamma$铀的不同相随温度的变化。这项研究利用了以前开发的三种不同的原子间电势：U MEAM，U-Zr MEAM和U-Mo ADP。阈值位移能量$\gamma ü$对于U MEAM，U-Zr MEAM和U-Mo ADP电位，在800 K时为73.2 eV，47.1 eV和35.6 eV。分别。阈值位移能量为$\alpha$对于U-Mo ADP，在600 K时的U为66.3 eV。