黄丹;熊剑;郭乙木;

• 1:河海大学工程力学系
• 2:南昌长力钢铁股份有限公司
• 3:浙江大学力学系 江苏南京210098
• 4:江西南昌330012

摘要(Abstract)：

建立原子尺度模拟三维立方晶格纳米单晶金属固体力学行为的物理模型,基于修正的镶嵌原子势,采用分子动力学方法分析面心立方晶格(FCC)镍和体心立方晶格(BCC)α-铁三维纳米单晶固体在拉伸和剪切载荷作用下的变形破坏,得到两种不同立方晶格三维纳米单晶固体的力学性能,与实验现象和结果吻合。研究表明晶格结构影响纳米晶固体的拉伸变形机制,FCC纳米单晶固体的拉伸变形以定向滑移为主,拉伸破坏存在短暂屈服阶段,有明显弹性模量软化现象;BCC纳米单晶固体的拉伸变形出现原子堆垛,存在较长屈服阶段,延性高于FCC纳米固体,而弹性模量小于后者。FCC纳米单晶固体的剪切模量小于拉伸模量,剪切强度小于拉伸强度,BCC纳米固体则相反。

关键词(KeyWords)： 纳米单晶固体;力学性能;原子模拟;变形破坏

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金(50539090);; 河海大学引进人才科研基金;; 河海大学自然科学基金(2007418311)

作者(Author): 黄丹;熊剑;郭乙木;

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DOI:

参考文献(References)：

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