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To study the mechanical properties of the film/substrate structure, the finite element code ABAQUS v6.9-1 is adopted to simulate the tensile mechanical behavior of the nanoscale thin film bonded to a substrate. The bifurcation phenomenon of the structure under uniaxial tension is found: the single-neck deformation, the multiple-neck deformation and the uniform deformation. The substrate and the film are regarded as power-hardening materials obeying the J 2 deformation theory. Firstly, the influence of material hardening match on tensile bifurcation mode is analyzed under perfectly well-bonded interface condition. Then, the effects of interfacial stiffness and other superficial defects surrounding the imperfection on bifurcation mode are investigated. It is concluded that under the well-bonded interface condition, if the stress of the substrate is larger than the film, the film will uniformly deform with the substrate; if the stress of the substrate is smaller than the film, the film will form a single neck, except the case that a weakly-hardening film is bonded to a steeply-hardening substrate when multiple necks can be formed. With the decrease of interfacial stiffness, the uniform deformation mode can transform into the multiple-neck deformation mode, and further transform into the single-neck deformation mode. And other defects surrounding the imperfection can influence the wavelength of deformation and neck number. 相似文献
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李林安 《湖南师范大学社会科学学报》1993,(6)
从本世纪40年代美国耗资逾20亿美元、动员15万科技人员研制原子武器的“曼哈顿工程”开始,科学研究活动便走上了一条规模浩大、社会化协作性强的道路。而当科学完全成为一种社会的活动以后,离开了社会的理解和支持,离开了社会式的管理,企求科学的发展则是很难想象的;同时,科学对技术、对社会生产和经济活动以及社会的方方面面,也都成为不可缺少 相似文献
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