分子动力学模拟纳米镍单晶的表面效应  

MOLECULAR DYNAMICS SIMULATION ON SURFACE EFFECTS OF MONOCRYSTALLINE NICKEL

作　　者：黄丹[1] 陶伟明[1] 郭乙木[1] 

机构地区：[1]浙江大学力学系固体力学研究所,杭州310027

出　　处：《固体力学学报》2005年第2期241-244,共4页Chinese Journal of Solid Mechanics

基　　金：国家自然科学基金(10302025);教育部回国人员启动基金(J20030151)资助.

摘　　要：对单晶镍纳米丝、纳米薄膜零温准静态拉伸破坏过程进行了分子动力学模拟.模拟表明表面效应对单晶纳米材料的原子运动及整体力学行为有显著影响.自由表面增加纳米材料的塑性、降低其强度,影响纳米材料的变形机制.受表面效应的作用,纳米镍丝强度与弹性模量均低于纳米镍薄膜.纳米薄膜的断裂接近脆性断裂,断裂强度符合Griffith理想晶体脆断理论;纳米镍丝在断裂过程中表现出微弱塑性.With Embedded Atom Method, the surface effects of monocrystalline nickel wire and nickel film under uniaxial tension are studied by Molecular Dynamics. With more free surfaces, the atomic energy and stress, strength and elastic modulus of nickel wire are all lower than that of nickel film, but the plasticity of the former is higher than the latter. The rupture of nano film is more like brittle fracture and accords with Griffith theory of rupture, but that of nano wire is more like tough fracture with plastic flow.

关 键 词：分子动力学 纳米镍单晶 表面效应 弹性模量 

分 类 号：TB383[一般工业技术—材料科学与工程]