论文标题
一致评估石墨烯的连续尺度特性
Consistent evaluation of continuum scale properties of Graphene
论文作者
论文摘要
我们使用连续力学触手统计力学，以开发一种方法，以一致评估石墨烯的连续尺度性能。该范围仅限于弹性模量，$ e $，据报道在0.912 tpa至7 tpa之间，泊松比，$ν$，据报道，$ν$从负面到0.46的价值，且有效的厚度，$ q $，其值在0.75Å到0.75Å到3.41岁之间。由于对这些特性的评估不一致以及在原子量表上可能无效的假设，因此出现了如此大的散射。我们的方法结合了三种独立的方法 - 单轴张力，倍轴张力和简单支撑纸的平面外振动，当在MD中串联使用时，它们可以提供$ e，ν$和$ q $的一致值。本研究中唯一的假设是连续尺度薄板振动方程的有效性，以表示长石墨烯片的自由振动。我们的结果表明 - （i）石墨烯是辅助烯，其泊松比随温度的升高而增加，（ii）随着温度的升高，$ e $降低，（iii）有效厚度随温度而增加。
We handshake statistical mechanics with continuum mechanics to develop a methodology for consistent evaluation of the continuum scale properties of graphene. The scope is kept limited to elastic modulus, $E$, which has been reported to vary between 0.912 TPa to 7 TPa, Poisson's ratio, $ν$, which has been reported to vary from being negative to a value as large as 0.46, and effective thickness, $q$, whose value varies between 0.75 Åto 3.41 Å. Such a large scatter arises due to inconsistent evaluation of these properties and making assumptions that may not be valid at atomistic scales. Our methodology combines three separate methods -- uniaxial tension, equibiaxial tension, and flexural out-of-plane free vibrations of simply supported sheets, which, when used in tandem in MD, can provide consistent values of $E, ν$ and $q$. The only assumption made in the present study is the validity of the continuum scale thin plate vibration equation to represent the free vibrations of a long graphene sheet. Our results suggest that -- (i) graphene is auxetic with its Poisson's ratio increasing with increasing temperature, (ii) with increasing temperature, $E$ decreases, and (iii) the effective thickness increases with temperature.
