• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Nanotechnology >On the real-time atomistic deformation of nano twinned CrCoFeNi high entropy alloy
【24h】

On the real-time atomistic deformation of nano twinned CrCoFeNi high entropy alloy

机译：论纳米孪晶CRCOFENI高熵合金的实时原子变形

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

High entropy alloys (HEAs) holding several principal elements in high concentration have unprecedented combination properties. The design of strong and highly ductile HEAs has attracted extensive attention from researchers in the last decade, such as in mechanisms for inducing different types of phase and nano-sized precipitates. Since some HEAs have low stacking fault energy, nanotwins can form during the plastic deformation process or magnetron sputtering, resulting in enhanced mechanical properties due to the existence of twin boundaries. The addition of twin boundaries is implied to be a promising method in engineering HEAs. Understanding how these twin boundaries affect the mechanical properties of nanotwinned HEAs is the key to designing strong and ductile examples. In this study, we performed a large-scale molecular dynamic simulation to investigate the mechanical properties of HEAs with different twin boundary spacings at various temperatures. The results show that the strength of HEAs at all tested temperatures increases with decreasing twin boundary spacing until a lower critical value of 1.83 nm is reached, which is close to the experimental value (2 nm). The strength of the HEAs at all tested temperatures decreases as the twin boundary spacing is decreased further. The dislocation motion transitions at the critical twin boundary spacing. In the sample with a twin boundary spacing bigger than 1.83 nm, Shockley dislocations tend to intersect the twin boundaries and glide in the hardening modes; on the other hand, Shockley dislocations travel along the direction parallel to the twin boundaries in samples with a twin boundary spacing smaller than 1.83 nm, leading to detwinning and softening in the HEAs. The dislocation motion and entanglement at 1 K are respectively slower and stronger than those at 300 K; the grain boundary activity is more obvious at a higher temperature. A mechanistic theoretical model together with a Hall-Petch relationship is then proposed to consider the coupled twin boundary and temperature effect on the deformation of nanotwinned HEAs.
机译：高浓度高浓度的高熵合金（HEA）具有前所未有的组合性能。强大和高度直率的杰斯的设计引起了过去十年的研究人员的广泛关注，例如在诱导不同类型的相和纳米大小沉淀的机制中。由于一些HEA具有低堆叠故障能量，因此在塑性变形过程或磁控溅射期间可以形成纳米管，导致由于双界的存在而增加的机械性能。暗示双界的增加是在艾莎工程中的一种有希望的方法。了解这些双界如何影响纳米丝的机械性能是设计强大和延展实例的关键。在这项研究中，我们进行了大规模的分子动态模拟，以研究SEA的机械性能与各种温度不同的双边界间距。结果表明，在所有测试温度下批发的强度随着双边界间隔的降低而增加，直到达到较低的临界值为1.83nm，这与实验值（2nm）接近。当双边边界间距进一步降低时，所有测试温度都降低了批发的强度。脱位运动在临界双边界间距处转换。在具有大于1.83nm的双边界间距的样品中，Shockley脱位倾向于与硬化模式相交，并在硬化模式下滑动;另一方面，震撼脱位沿着与小于1.83nm小于1.83nm的双边界间距的样品平行的方向行进，导致钩子中的扭转和软化。 1 k的位错运动和缠结分别比300 k的速度较慢，更强大;在较高温度下，晶界活动更加明显。然后提出了一种机械理论模型以及霍尔 - 矛盾关系，以考虑耦合的双边界和对纳米丝掺杂的变形的影响。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号