Effect of Zr additions on crystal structures and mechanical properties of binary W–Zr alloys: A first-principles study

• Published in: Journal of materials research 2019-01, Vol.34 (2), p.290-300
• Main Authors: Diyou, Jiang, Li, Xue, Xuemei, Huang, Tao, Wang, Jianfeng, Hu
• Format: Article
• Language: English
• Subjects: Alloying effects; Annealing; Applied and Technical Physics; Approximation; Binary alloys; Biomaterials; Brittleness; Composite materials; Computer simulation; Crystal structure; Ductility; Elastic properties; Energy; First principles; Free energy; Fusion; Grain boundaries; Grain growth; Heat conductivity; Heat of formation; High temperature; Inorganic Chemistry; Lattice parameters; Materials Engineering; Materials research; Materials Science; Mechanical properties; Metals; Modulus of elasticity; Molybdenum; Nanotechnology; Nuclear reactors; Plasma sintering; Principles; Radiation; Theory; Zirconium alloys; Zirconium base alloys
• ISSN: 0884-2914; 2044-5326
• DOI: 10.1557/jmr.2018.426

The effect of zirconium alloying on the crystal structures and mechanical properties of binary tungsten–zirconium alloys is investigated in this study using the first-principles method. Firstly, we investigate the cell volumes, lattice constants, and formation energies of binary W1−xZrx (x = 0, 0.0625, 0.125, 0.1875, 0.25, and 0.5) alloys. It is shown that binary tungsten–zirconium alloys maintain BCC structures. When the concentration of zirconium atoms is lower than 12.5%, the structures of binary tungsten–zirconium alloys can be thermodynamically stable. The elastic constants of binary tungsten–zirconium alloys are calculated based on the optimized atomic lattice. Then, the elastic modulus and other mechanical parameters are deduced according to the relevant formulas. It is shown that the mechanical strength of binary tungsten–zirconium alloy decreases with an increasing concentration of zirconium atoms, which is lower than the mechanical strength of pure tungsten metal. However, the mechanical strength of binary tungsten–zirconium alloys is higher than that of pure zirconium metal. In addition, zirconium alloying can be effective in improving the ductility of pure tungsten metal.