A Discrete Complex Compliance Spectra Model of the Nonlinear Viscoelastic Creep and Recovery of Microcellular Polymers
نویسندگان
چکیده
The present work reports a discrete stress-dependent, complex compliance spectra method that may be used to predict the mechanical response of nonlinear viscoelastic polymers during creep and recovery processes. The method is based on the observation that the real and imaginary parts of a discrete complex compliance frequency spectra obtained from creep and recovery measurements are smooth, easily fit functions of stress. The new method is applied to a set of microcellular polycarbonate materials with differing relative density. The nonlinear viscoelastic characteristics of a microcellular polycarbonate material system are very sensitive to relative density and therefore, this material system is a particularly difficult modeling challenge. However, the present model was able to exhibit excellent quantitative agreement with the basis creep and recovery measurements at all experimental stress levels for each of the experimental relative density material types. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 691–697, 2000
منابع مشابه
Study of the Influence of Multiple Step Creep/Creep-Recovery Loading on the Nonlinear Viscoelastic Response of Carbon Fiber Polymer Matrix Composites
In the current study the nonlinear viscoelastic response of a polymer matrix composite under multiple creep/creep-recovery loading is presented. The influence of creep/creep-recovery multiple step loading in the overall strain response both viscoelastic and viscoplastic is examined and an attempt for modeling this behaviour is attempted. An increase in the parameters of nonlinearity is observed...
متن کاملViscoelastic Modeling of the Recovery Behavior of Cut Pile Carpet After Static Loading: A Comparison Between Linearand Nonlinear Models
متن کامل
Creep Strain and Stress Analysis in Laminated Composite Pres-sure Vessels
This study investigates the time-dependent long-term creep strain in a composite cylinder made of glass/vinylester with a unidirectional ply. The cylinder is subjected to an internal pressure and the boundary condition is free–free and acts as thermal insulation. The classical lamination theory (CLT) is used to derive the governing equations as a second-order equation to determine the radial, c...
متن کاملA Nano-indentation Identification Technique for Viscoelastic Constitutive Characteristics of Periodontal Ligaments
Introduction: Nano-indentation has recently been employed as a powerful tool for determining the mechanical properties of biological tissues on nano and micro scales. A majority of soft biological tissues such as ligaments and tendons exhibit viscoelastic or time-dependent behaviors. The constitutive characterization of soft tissues is among very important subjects in clinical medicine and espe...
متن کاملNonlinear viscoelastic characterization of bovine trabecular bone
The time-independent elastic properties of trabecular bone have been extensively investigated, and several stiffness-density relations have been proposed. Although it is recognized that trabecular bone exhibits time-dependent mechanical behaviour, a property of viscoelastic materials, the characterization of this behaviour has received limited attention. The objective of the present study was t...
متن کامل