Chemical and Materials Engineering, University of Nevada, Reno, NV, USA.
Shock and Detonation Physics, Los Alamos National Laboratory, Los Alamos, NM, USA.
Sci Rep. 2017 Aug 15;7(1):8264. doi: 10.1038/s41598-017-08302-5.
Magnesium has attracted attention worldwide because it is the lightest structural metal. However, a high strength-to-weight ratio remains its only attribute, since an intrinsic lack of strength, ductility and low melting temperature severely restricts practical applications of Mg. Through interface strains, the crystal structure of Mg can be transformed and stabilized from a simple hexagonal (hexagonal close packed hcp) to body center cubic (bcc) crystal structure at ambient pressures. We demonstrate that when introduced into a nanocomposite bcc Mg is far more ductile, 50% stronger, and retains its strength after extended exposure to 200 C, which is 0.5 times its homologous temperature. These findings reveal an alternative solution to obtaining lightweight metals critically needed for future energy efficiency and fuel savings.
镁因其是最轻的结构金属而引起了全世界的关注。然而，高强度与重量比仍是其唯一的特性，因为强度、延展性和低熔点的固有缺乏严重限制了镁的实际应用。通过界面应变，可以将 Mg 的晶体结构从简单的六方（密排六方 hcp）转变并稳定为体心立方（bcc）晶体结构，在环境压力下。我们证明，当将其引入纳米复合材料 bcc 中时，Mg 的延展性提高了 50%，强度提高了 50%，并且在延长暴露于 200°C 后仍保持其强度，这是其同系温度的 0.5 倍。这些发现为获得未来能源效率和燃料节省所需的轻量化金属提供了一种替代解决方案。
