The mechanical behavior of highly oriented pyrolyti c graphite (HOPG) has been investigated in this paper, by simulating a machining p rocess in a nano-indent test with the method of molecular dynamics (MD) and by doi...The mechanical behavior of highly oriented pyrolyti c graphite (HOPG) has been investigated in this paper, by simulating a machining p rocess in a nano-indent test with the method of molecular dynamics (MD) and by doing an experiment directly using the probe tip of atomic force microscope (AFM ) as tool. The characteristics and properties of graphite crystal lattice are di scussed firstly, then, three potentials are selected for different interaction b etween graphite atoms according to the graphite properties, and molecular dynami c calculations of nano-indent test are carried out. After that, an experiments for nano-indentation of graphite crystal and its observation, directly by using an AFM tip as indent tool and consequential measurement, are introduced and don e. The topography of the hole indented by the tip, the profile, surface of the g raphite, as well the indented force and the strength of HOPG are measured and ca lculated. Results show the indentation experiment and the MD calculation consist ent with each other, that MD may be a good tool for comprehending the micro-mac hining behavior and the mechanism of materials.展开更多
文摘The mechanical behavior of highly oriented pyrolyti c graphite (HOPG) has been investigated in this paper, by simulating a machining p rocess in a nano-indent test with the method of molecular dynamics (MD) and by doing an experiment directly using the probe tip of atomic force microscope (AFM ) as tool. The characteristics and properties of graphite crystal lattice are di scussed firstly, then, three potentials are selected for different interaction b etween graphite atoms according to the graphite properties, and molecular dynami c calculations of nano-indent test are carried out. After that, an experiments for nano-indentation of graphite crystal and its observation, directly by using an AFM tip as indent tool and consequential measurement, are introduced and don e. The topography of the hole indented by the tip, the profile, surface of the g raphite, as well the indented force and the strength of HOPG are measured and ca lculated. Results show the indentation experiment and the MD calculation consist ent with each other, that MD may be a good tool for comprehending the micro-mac hining behavior and the mechanism of materials.