On determination of the damping factor of linear viscoelastic materials using dynamic indentation:a theoretical study  

作　　者：CAO YanPing JI XiangYing FENG XiQiao 

机构地区：[1]Applied Mechanics Lab, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China

出　　处：《Science China(Physics,Mechanics & Astronomy)》2011年第4期598-605,共8页中国科学：物理学、力学、天文学（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos. 10972112,10525210,and 10732050);the National Basic Research Program of China(Grant Nos. 2010CB631005)

摘　　要：In this study,we theoretically investigate the dynamic indentation for measuring the loss (damping) factor of a linear viscoelastic material from its indentation response.A rigid indenter with arbitrary tip profile is assumed to indent into a viscoelastic substrate with arbitrary shape.We perform a theoretical analysis and identify the conditions under which the loss factor of the material can be determined from the phase angle between the applied harmonic indentation load and the corresponding harmonic displacement,a directly measurable quantity in a dynamic indentation test.To validate the conclusion drawn from our theoretical analysis,a series of numerical experiments are performed,including the spherical indentation of a soft layer with irregular surface morphology bonded to a rigid substrate,a conical indenter with tip defects indenting into a half-spherical particle,and the indentation of porous materials.This study may facilitate the use of the dynamic indentation technique to evaluate the damping properties of linear viscoelastic materials,including some advanced polymers and biological soft tissues.In this study, we theoretically investigate the dynamic indentation for measuring the loss （damping） factor of a linear visco- elastic material from its indentation response. A rigid indenter with arbitrary tip profile is assumed to indent into a viscoelastic substrate with arbitrary shape. We perform a theoretical analysis and identify the conditions under which the loss factor of the material can be determined from the phase angle between the applied harmonic indentation load and the corresponding har- monic displacement, a directly measurable quantity in a dynamic indentation test. To validate the conclusion drawn from our theoretical analysis, a series of numerical experiments are performed, including the spherical indentation of a soft layer with irregular surface morphology bonded to a rigid substrate, a conical indenter with tip defects indenting into a half-spherical par- ticle, and the indentation of porous materials. This study may facilitate the use of the dynamic indentation technique to evaluate the damping properties of linear viscoelastic materials, including some advanced polymers and biological soft tissues.

关 键 词：dynamic indentation damping properties viscoelastic materials f＇mite element simulation 

分 类 号：TB301[一般工业技术—材料科学与工程] TQ171.1[化学工程—玻璃工业]