Molecular Dynamics Study Of Surface Scratch Behavior Of Nickel/Copper Bilayer Nanofilm

With the development of nano-science and nano-technology,electronic devices tend to be miniaturized.The metal nanofilm attracts extensive attention and has been applied in many areas such as microelectronic mechanical systems,aerospace,optics,electromagnetism and medical instruments etc..During the precise processing,assembling and utilization of nanofilm,the surface scratch is unavoidable.It results in damage or wear on the surface thus degrades the serviceability and reliability of equipment.It is necessary to study the scratch behavior of metal nanofilm.As a protective layer,the metallic nickel nanofilm can improve durability and scratch resistance.The nickel/copper bilayer nanofilm has been widely adopted.In the numerical simulation of the metal bilayer nanofilm,the substrate surface is generally simplified as perfect smooth.In reality,the surface cannot achieve absolute smoothness.Therefore,the possible effect of the surface roughness or texture of the substrate copper film on nano-scratch response has to be studied.The effect of different working conditions on the of nickel/copper bilayer nanofilm are also investigated using molecular dynamics(MD)simulation.With understanding of the influence of the substrate texture on the nanoscratch behavior of the nickel/copper bilayer nanofilm,a theoretical guidance for improving the precision machining quality can be obtained.To study the scratch behavior of nickel/copper bilayer nanofilm,the following works are carried out:(1)A MD model of the nickel/copper bilayer nanofilm with different textures on the substrate copper film surface is established,and the nanoscratch simulation is performed.(2)For different types of the substrate texture,the effects of tool radius and scratch depth on the scratch response and deformation of the nickel/copper bilayer nanofilm are investigated.(3)For different density of a specific substrate texture,the effects of tool radius and scratch depth on the scratch response and deformation of the nickel/copper bilayer nanofilm are investigated.