基于气压鼓泡法研究石墨烯力学性能  

Mechanical Properties Characterization of Graphene via Pressure Bulge Testing

作　　者：安飞 曹国鑫 AN Fei;CAO Guoxin(School of Aerospace Engineering and Applied Mechanics,Tongji University,Shanghai 200092,China)

机构地区：[1]同济大学航空航天与力学学院,上海200092

出　　处：《力学季刊》2023年第1期56-64,共9页Chinese Quarterly of Mechanics

基　　金：国家自然科学基金(11972258)。

摘　　要：通常假设二维材料为连续介质薄膜,然后采用连续介质薄膜的研究方法进行二维材料力学性能研究,其中气压鼓泡法是一种主要测试方法.但实验观测发现,悬空石墨烯并非处于气压鼓泡测试分析模型中假设的固支边界条件,而是处于一种粘附边界条件:靠近孔壁边界处,有小部分材料通过范德华吸引粘附在基底柱形孔的侧壁上,而且粘附部分可以在极小载荷作用下剥离.这导致石墨烯悬空部分的实际半径大于基底孔半径,即鼓泡实验中的石墨烯是一种松弛薄膜,而非通常认为的预拉伸薄膜.通过有限元数值模拟研究发现,可基于含有名义松弛应变的鼓泡分析模型获得处于粘附边界条件下的石墨烯弹性模量.It is generally assumed that the two-dimensional material is a continuum film,and then the research method of continuum film is used to study the mechanical properties of the two-dimensional material.The pressure bulge testing is one of the main test methods for characterizing the mechanical properties of thin film,which has been used to measure the elastic modulus of graphene.However,the experimental observation shows that the suspended graphene is not in the clamped boundary condition assumed in the existing analytical model adopted in pressure bulge testing,but in the adhesive boundary condition:a small part of the material close to the boundary of the cylindrical hole adheres to the side wall of the substrate cylindrical hole through van der Waals attraction,and the adhesion part can be peeled off under a small load.Consequently,the actual radius of the suspended part of graphene is larger than the radius of the substrate hole,namely,graphene in the pressure bulge testing is a slack film rather than a pre-stretched film.Using finite element simulation,it is found that the elastic modulus of graphene under the adhesion boundary condition can be accurately determined using the pressure bulge testing based on the analytical model considering the apparent residual strain.

关 键 词：石墨烯 鼓泡法 弹性模量 

分 类 号：TU311.4[建筑科学—结构工程] O241.82[理学—计算数学]