热力耦合作用下石墨烯力学特性的研究

项目名称： 热力耦合作用下石墨烯力学特性的研究

项目编号： No.11204031

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 物理学I

项目作者： 陈坚

作者单位： 东南大学

项目金额： 30万元

中文摘要： 石墨烯具有极其优异的力学性能，如弹性模量达到1Ta、断裂强度接近理论强度值，可应用于纳米机电系统、质量传感膜和柔性电子系统等领域。但由于缺乏有效的测试手段，对二维尺度石墨烯力学性质的表征局限在常温状态。分子动力学计算结果显示：温度改变将导致其力学性能的显著变化。随着石墨烯在越来越多领域显示出广泛的应用价值，如电子、能源和材料等，准确评价其在非常温条件下的力学特性显得尤为重要。本项目拟采用新型非常温纳米压痕仪系统地研究热力耦合条件下（低温段：-15oC至室温；高温段：室温至500oC）石墨烯力学特性，包括弹性模量，断裂强度及本构关系；基于连续介质力学建立相关理论模型；探讨纳米尺度材料可能具有的异常物理现象及其本征特性；研发相应的薄膜材料力学性能测试新方法和新技术。最终研究结果有望揭示石墨烯在热力耦合条件下的力学特性和失效规律，为其在非常温环境下的应用提供力学实验数据和理论基础。

中文关键词： 石墨烯；纳米压入；力学性能；热力耦合；连续介质力学

英文摘要： Graphene exhibits excellent mechanical properties, for example, its Young's modulus is as high as ~1TPa and the fracture strength can reach the theoretic value. Researchers thus predicted that graphene can be used in various applications such as nanoelectromechanical system, mass sensor membrane and flexible electronics, etc. However, the mechanical characterization technique for graphene was limited to the ambient condition due to the lack of the efficient instruments. According to molecular dynamic calculations, the service temperature can result in a significant change of the mechanical properties of graphene. With its potential applications in increasing fields, such as information, energy and materials etc, it is important to obtain the mechanical properties of graphene at non-ambient temperatures. The aims of this project are to systematically study the mechanical characteristcs of graphene inlcuding Young's modulus, fracture strength and constitutive relations, under thermo-mechanical coupling conditions (low temperature range: -15oC to room temperature; high temperature range: room temperature to 500oC) using a novel nanoindentation system with high/low temperature capacities, to establish the theoretic model based on the continuum mechanics,to study the possible abnormal physical phenomena and its intri

英文关键词： graphene；nanoindentation；mechanical properties；thermomechanical coupling；continuum mechanics