纸力学特性尺寸效应及其理论模型  

Size Effect of Mechanical Properties of Paper and Its Theoretical Model

作　　者：张慧梅[1] 朱峰波 刘小宇 刘洋[2] ZHANG Hui-mei;ZHU Feng-bo;LIU Xiao-yu;LIU Yang(College of Science,Xi’an University of Science and Technology,Xi’an 710054,China;College of Geology and Environment,Xi’an University of Science and Technology,Xi’an 710054,China)

机构地区：[1]西安科技大学理学院,西安710054 [2]西安科技大学地质与环境学院,西安710054

出　　处：《科学技术与工程》2025年第6期2284-2292,共9页Science Technology and Engineering

基　　金：国家自然科学基金(12172280,52268047,51868075);陕西省自然科学基金重点项目(2020JZ-53)。

摘　　要：纸或纸基材料在使用和服役时对其力学特性有一定要求,但是现有尺寸效应实验和理论说明不同尺寸试样力学特性并不相同,因此明确其力学特性的尺寸效应对于保证其安全非常必要。选用易于获取且强度较高的牛皮纸为研究材料,开展了不同尺寸试样单轴拉伸试验,确定力学特性及其离散性随试样尺寸的变化规律。分析了不同尺寸牛皮纸受力变形特征和宏微观破坏特征,揭示牛皮纸力学特性尺寸效应内在机理。最后建立了牛皮纸力学特性尺寸效应模型。研究发现:牛皮纸名义拉伸强度和名义峰值应变随尺寸增大先增大后下降,这是因为切断的边缘纤维造成牛皮纸试样边缘承受应力和应变能力较弱,而小尺寸试样中弱化边缘占比较大,导致名义拉伸强度和名义峰值应变呈现上升尺寸效应;大尺寸试样中,弱化边缘占比可以忽略,内部断裂过程区起主导作用,导致名义拉伸强度和名义峰值应变呈下降尺寸效应。建立的边缘-内部断裂过程区尺寸效应模型能较好地描述牛皮纸名义拉伸强度和名义峰值应变的尺寸效应,但是其不能体现名义拉伸强度和名义峰值应变上升尺寸效应阶段的非线性特征。There are certain requirements for the mechanical properties of paper or paper-based materials during their service.However,existing experimental and theoretical studies of size effects indicate that the mechanical properties of specimens with different sizes are not identical.Therefore,it is necessary to clarify the size effect of their mechanical properties to ensure their safety.The kraft paper,which is easy to obtain and has high strength,was selected to carry out uniaxial tensile tests on with different sizes.And then the size effects of mechanical properties and their dispersions were determined.By analyzing the deformation characteristics and macro-microscopic damage features of different sizes specimens,the intrinsic mechanism of the size effect on the mechanical properties of kraft paper was revealed.Finally,a size effect model of mechanical properties for kraft paper was established.The study finds that the nominal tensile strength and nominal peak strain of kraft paper first increase and then decrease as the sizes increases.This is because the cut edge fibers cause the edges of the kraft paper specimens to have weaker stress and strain capabilities,and the proportion of weakened edges in small-sized specimens is relatively large,leading to an increasing size effect on the nominal tensile strength and nominal peak strain.In large-sized specimens,the proportion of weakened edges can be ignored,and the internal fracture process zone plays a dominant role,leading to a decreasing size effect on the nominal tensile strength and nominal peak strain.The established edge-internal fracture process zone size effect model can well describe the size effect on the nominal tensile strength and nominal peak strain of kraft paper.However,this model cannot capture the nonlinear characteristics of the increasing size effect stage for the nominal tensile strength and nominal peak strain.

关 键 词：纸 力学特性 尺寸效应 弱化边缘 理论模型 

分 类 号：TB301[一般工业技术—材料科学与工程]