徐喻琼;马小强;

• 1:三峡大学水电机械设备设计与维护湖北省重点实验室

摘要(Abstract)：

采用分子动力学模拟方法研究不同晶粒尺寸多晶钨纳米线在拉伸过程中的应力-应变行为,详细分析晶粒尺寸对应力-应变曲线模式、弹性模量及拉伸变形机理的影响。结果表明:晶粒尺寸在(5.303～7.653)nm内的多晶钨纳米线的应力-应变曲线中存在双峰、单峰;弹性模量随晶粒尺寸的增大而增加;拉伸力学性能呈反向Hall-Petch关系;塑性变形主要在晶界处,并伴随晶粒转动;应变量达0.15时,纳米线中观察到孪晶组织;随着应变量增加,出现孪晶滑移,且孪晶附近出现局部应力集中,导致断裂。

关键词(KeyWords)： 多晶纳米线;拉伸变形;塑性变形机理;分子动力学

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金(11204158)

作者(Author): 徐喻琼;马小强;

Email:

DOI: 10.14024/j.cnki.1004-244x.20190516.003

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