可穿戴石墨烯复合材料压阻传感性能计算方法及其参数分析  

Computational method and parameters analysis of piezoresistive sensing properties of wearable graphene composites

作　　者：李正 尚军军 刘夏[1] 杨庆生[1] LI Zheng;SHANG Junjun;LIU Xia;YANG Qingsheng(Department of Mechanics,Beijing University of Technology,Beijing 100124,China)

机构地区：[1]北京工业大学力学系,北京100124

出　　处：《复合材料学报》2021年第4期1066-1075,共10页Acta Materiae Compositae Sinica

基　　金：国家自然科学基金(11772012,11932002)。

摘　　要：随机堆叠石墨烯制成的石墨烯复合材料(GC)的不均匀性,使得GC的压阻传感性能与其细观单元的尺寸密切相关。根据GC的微观结构特点,发展了一种GC压阻传感性能计算方法,依次计算了GC的电子渗流概率、初始方阻和相对电阻-应变关系。结果表明:GC的电子渗流概率随着石墨烯面分比的增大而增大,大长宽比石墨烯组成的GC的渗流阈值更低,电子迁移网络连通的最小面分比是0.5;GC代表单元的最小边长可由它的初始方阻确定,大面分比GC拥有更小的代表单元,当石墨烯面分比分别为1.2、1.4、1.6、1.8、2.0时,GC代表单元的最小边长与石墨烯边长的比值为35、30、25、20、15。最后,不同石墨烯面分比、长宽比的GC代表单元的计算结果证实,增大石墨烯的面分比与长宽比能够延长GC的线性感知阶段,提高GC的总感知范围。Due to the inhomogeneity of graphene composites(GC)made of randomly stacked graphene,the piezoresistive sensing performance of GC is closely related to the size of meso element.According to the microstructure characteristics of GC,a calculation method for piezoresistive sensing performance of GC was developed.The electron percolation probability,initial sheet resistance and relative resistance-strain relationship of GC were calculated in turn.The results show that the electron percolation probability of GC increases with the increase of graphene area fraction.The percolation threshold of GC with large aspect ratio graphene is lower,and the minimum area fraction of graphene to keep the electron transport network connected is 0.5.The minimum side length of GC representative element can be determined by its initial sheet resistance.GC with large area fraction has smaller representative element,and the minimum ratios of the side length of representative element with area fraction of1.2,1.4,1.6,1.8 and 2.0 to graphene side length are 35,30,25,20 and 15,respectively.Finally,the calculation results of GC representative elements confirm that the linear sensing stage and total sensing range of GC can be enlarged by increasing the area fraction or aspect ratio of graphene.

关 键 词：石墨烯 复合材料 渗流阈值 代表单元 压阻性能 

分 类 号：TB332[一般工业技术—材料科学与工程]