Prediction of novel final phases in aged uranium-niobium alloys

التفاصيل البيبلوغرافية
العنوان: Prediction of novel final phases in aged uranium-niobium alloys
المؤلفون: Pan, Xiao L., Wang, Hao, Zhang, Lei L., Wang, Yu F., Chen, Xiang R., Geng, Hua Y., Chen, Ying
المصدر: Journal of Nuclear Materials 579 (2023) 154394
سنة النشر: 2023
المجموعة: Condensed Matter
Physics (Other)
مصطلحات موضوعية: Condensed Matter - Materials Science, Condensed Matter - Strongly Correlated Electrons, Physics - Applied Physics, Physics - Computational Physics
الوصف: Ordered intermetallics are long believed to be the final products of the aging of U-Nb solid solutions at low temperatures, a crucial property for the practical applications of this alloy in engineering and industry. However, such conjectured ordered compounds have not been experimentally or theoretically established. Herein, numerical evidence for ordered intermetallic U-Nb compounds is presented using thorough first-principles structure predictions up to 500 GPa. Two stable U2Nb compounds and one metastable U2Nb and one metastable U3Nb were discovered. A unique hybridized transition driven by pressure was observed in U2Nb, which is a superposition of one first-order transition and another second-order transition, leading to striking features near the transition pressure of 21.6 GPa. The decomposition limit of these compounds at high temperature was also investigated. The strong stability of U2Nb in the region of low pressure and high temperature was revealed. This discovery of ordered U2Nb and its strong stability over a wide pressure range completely changed the phase diagram of U-Nb alloys and shed new light on the dynamic response and aging mechanism of U-Nb alloys.
Comment: 21 pages, 16 figures, with Supplementary Material
نوع الوثيقة: Working Paper
DOI: 10.1016/j.jnucmat.2023.154394
الوصول الحر: http://arxiv.org/abs/2303.14442Test
رقم الانضمام: edsarx.2303.14442
قاعدة البيانات: arXiv