纳米尺度的应力计算方法包括维里应力和工程应力的计算方法.作者以计算固体中的拉伸应力为例,阐述两种计算方法在计算固体中应力时的异同及适用范围.比较两种算法在计算垂直于拉伸方向截面上的平均拉伸应力和在该截面上不同位置处的局部拉伸应力,分析在不同外载荷下两种方法的计算结果,最后总结出两种算法各自的优点和缺点.在具体计算中,选取了EAM势函数,用分子动力学方法对纳米单晶铜杆的拉伸过程进行模拟.
Virial stress and engineering stress are calculated by two nano-scale stress calculation methods. This paper describes the definitions and differences of these two methods. Based on the numerical results of tensile test of single-crystalline nano-scale copper bar, the average and local tensile stresses are compared, the advantages and disadvantages of these two methods are discussed in detail. Different external loads are considered during the simulations. The tensile test is simulated by molecular dynamics method, and the EAM potential function is adopted.
参考文献
| [1] | Irving J H;Kirkwood J G .The statistical mechanical theory of transport processes IV The equations of hydrodynamics[J].Chemical Physics,1950,18:817-829. |
| [2] | Cormier J.;Delph TJ.;Rickman JM. .Stress calculation in atomistic simulations of perfect and imperfect solids[J].Journal of Applied Physics,2001(1):99-104. |
| [3] | Lutsko J F .Stress and elastic constants in anisotropic solids:molecular dynamics techniques[J].J of Apply Physics,1988,64(03):1152-1154. |
| [4] | Tsai D H.The virial theorem and stress calculation in molecular dynamics[M].Nation Bureau of Standards,Washington,1979:1375-1382. |
| [5] | Cheung K S;Yip S .Atomic-level Stress in an inhomogenous system[J].Journal of Applied Physics,1991,70(10):5688-5690. |
| [6] | Zhou M .The virial stress is not a measure of mechanical stress[J].Materials Research,2002,731:59-70. |
| [7] | Min Z. .A new look at the atomic level virial stress: on continuum-molecular system equivalence[J].Proceedings of the Royal Society. Mathematical, physical and engineering sciences,2003(2037):2347-2392. |
| [8] | Dommelen L V .Phsical Interpretation of the Virial Stress[J].The Royal Society,2004,317:132-139. |
| [9] | Doyama M;Kogure Y .Embedded atom potentials in fcc and bcc metals[J].Computational Materials Science,1999(1/4):80-83. |
| [10] | Wu HA .Molecular dynamics study on mechanics of metal nanowire[J].Mechanics research communications,2006(1):9-16. |
| [11] | Lutsko J F .Stress and elastic constants in anisotropic solids,Molecular Dynamics techniques[J].J of Apply Physics,1988,64(01):1152-1154. |
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