Premium
A physically motivated model for filled elastomers including strain rate and amplitude dependency in finite viscoelasticity
Author(s) -
Juhre Daniel,
Raghunath Rathan,
Klüppel Manfred
Publication year - 2015
Publication title -
pamm
Language(s) - English
Resource type - Journals
ISSN - 1617-7061
DOI - 10.1002/pamm.201510144
Subject(s) - viscoelasticity , materials science , composite material , elastomer , strain rate , deformation (meteorology) , natural rubber , dependency (uml) , hysteresis , relaxation (psychology) , physics , computer science , condensed matter physics , software engineering , psychology , social psychology
A microstructure‐based model of rubber reinforcement, the so‐called dynamic flocculation model (DFM), is presented describing filler‐induced stress softening and hysteresis by the breakdown and reaggregation of strained filler clusters [1]. An extension of this model allows to consider incomplete deformation cycles that occur in the simulation of arbitrary deformation histories [2]. Good agreement between measurement and the model is obtained for CB‐filled elastomers like NR, SBR or EPDM, loaded along various deformation histories. One very important aspect is that the model parameters can be directly referred to the physical properties. This benefit is used to extend the model to further essential effects like time‐ and rate‐dependent material behavior. In the limit range above the glass transition temperature these viscoelastic effects originate mainly from the filler‐filler interactions. In the material model these interactions are characterized by two material parameters s v and s d , respectively. The parameter s v defines the strength of the virgin filler cluster, whereas s d represents the strength according to the broken or damaged filler clusters. Both parameters can be defined as functions of time s v,d = ŝ v,d ( t ), which can be motivated by physical meaning [3]. Due to this extension it is possible to capture the very complex strain rate and amplitude dependency during loading and relaxation. (© 2015 Wiley‐VCH Verlag GmbH & Co. KGaA, Weinheim)