Viscoelastic behavior of plasticized polyvinyl chloride at large deformations. II. Creep

1963 ◽  
Vol 1 (8) ◽  
pp. 2511-2523 ◽  
Author(s):  
Raffaele Sabia ◽  
F. R. Eirich
1969 ◽  
Vol 42 (2) ◽  
pp. 373-380 ◽  
Author(s):  
G. W. Becker ◽  
H.-J. Rademacher

Abstract Stress relaxation at different strains, and retarded deformation at different stresses were measured for rod-shaped test specimens of plasticized PVC in tension. Temperature was varied in such a way that changes in properties of the material, within the entire range from the glassy-amorphous to the quasi rubber-elastic states, could be comprehended. From results of the two types of experiment it was concluded that outside of the linear stress region, and at all temperatures, the time and deformation dependence of stress could be separated, but this was not possible for the time and stress dependence of strain.


Author(s):  
E. L. Deladi ◽  
M. B. de Rooij ◽  
D. J. Schipper

Rubber-metal contact involves relatively large deformations and large real contact areas compared to metal-metal contact. Here, a deterministic model is proposed for the contact between rubber and metal surfaces, which takes into account the interaction between neighboring asperities. In this model, a description of the actual micro-contact is used instead of a summit which is a local maximum at the surface. Linear viscoelastic behavior, modeled by a three-element mechanical model, is assumed for the rubber. In the present model, the equations regarding the deformation due to a Hertzian pressure inside and outside the contact area have been modified for the viscoelastic case. The deterministic case is compared with the statistical one. Besides this, the deformation of the bulk material beneath the asperities is taken into account. The results reveal that the bulk deformation has a significant effect at higher nominal pressures.


1976 ◽  
Vol 15 (7-8) ◽  
pp. 367-378 ◽  
Author(s):  
W. V. Chang ◽  
R. Bloch ◽  
N. W. Tschoegl

1971 ◽  
Vol 38 (1) ◽  
pp. 30-38 ◽  
Author(s):  
K. Onaran ◽  
W. N. Findley

Kernel functions for mixed-time parameters in the multiple integral representation of the nonlinear viscoelastic behavior of polyvinyl chloride were determined from both two-step tension and two-step torsion creep experiments. First and second-order terms were used for tension and first and third-order terms were used for torsion to describe these kernel functions. Stepdown tests were needed for good accuracy of representation. Accuracy of prediction was good for stepdown but not stepup tests. The product form assumption for these kernel functions and the modified superposition method were also investigated. The latter gave the best overall predictability of the three methods, although the product form was nearly as satisfactory.


2014 ◽  
Vol 4 (6) ◽  
pp. 714-723 ◽  
Author(s):  
M. D. Monsia ◽  
Y. J. F. Kpomahou

The aim of this work is to propose a mathematical model in terms of an exact analytical solution that may be used in numerical simulation and prediction of oscillatory dynamics of a one-dimensional viscoelastic system experiencing large deformations response. The model is represented with the use of a mechanical oscillator consisting of an inertial body attached to a nonlinear viscoelastic spring. As a result, a second-order first-degree Painlevé equation has been obtained as a law, governing the nonlinear oscillatory dynamics of the viscoelastic system. Analytical resolution of the evolution equation predicts the existence of three solutions and hence three damping modes of free vibration well known in dynamics of viscoelastically damped oscillating systems. Following the specific values of damping strength, over-damped, critically-damped and under-damped solutions have been obtained. It is observed that the rate of decay is not only governed by the damping degree but, also by the magnitude of the stiffness nonlinearity controlling parameter. Computational simulations demonstrated that numerical solutions match analytical results very well. It is found that the developed mathematical model includes a nonlinear extension of the classical damped linear harmonic oscillator and incorporates the Lambert nonlinear oscillatory equation with well-known solutions as special case. Finally, the three damped responses of the current mathematical model devoted for representing mechanical systems undergoing large deformations and viscoelastic behavior are found to be asymptotically stable.


Sign in / Sign up

Export Citation Format

Share Document