Time-Dependent Mechanical Behaviors of Polyamide 6/Nano-SiO2 Composite
The uniaxial tension under various strain rates,creep under various sustained loads,and equalamplitude-strain loading and unloading tests are carried out at room temperature with polyamide 6/nano-SiO2 composite specimens.According to the elasticity recovery correspondence principle,the recovered elastic stresses (strains) in the case of prescribed strain (stress) history are calculated,and the instantaneous elastic constitutive equations are deduced.The nonlinear viscoelastic constitutive relations in single integral form on the basis of the instantaneous elastic constitutive equations are constructed and applied to model the current stress (strain) responses of polyamide 6/nano-SiO2 composite.The theoretic results agree well with the experimental data,which demonstrates that the single integral constitutive relations used in this work can accurately simulate the physical nonlinear viscoelastic properties of polyamide 6/nano-SiO2 composite.Finally,the creep curve at higher stress level is horizontally shifted along logarithmic timescale using a stress shift factor in terms of the time-stress superposition principle and superposed on that at relative lower stress level to form a master creep compliance curve that spans a longer timescale interval than the short-term test curve does,which suggests that TSSP provides an accelerated characterization method for the long-term creep performance ofpolyamide 6/nano-SiO2 composite.
Constitutive relation Viscoelasticity Creep Time-stress superposition principle
Zhao Rongguo Luo Wenbo
Institute of Fundamental Mechanics and Material Engineering,Xiangtan University,Hunan 411105,P.R.China;Key Laboratory of Low Dimensional Materials and Application Technology of Ministry of Education,Xiangtan University,Hunan 411105,P.R.China
国际会议
The Fifth China International Conference on High-Performance Ceramics (第五届先进陶瓷国际研讨会(CICC-5))
长沙
英文
1080-1083
2007-05-10（万方平台首次上网日期，不代表论文的发表时间）