Research
Constitutive Models for Rubbers
We study the emotions of materials. How does a material respond when subjected to an excitation? The response can depend on the history of excitation. On the other hand, the excitation can be stress or strain or even a change of thermodynamic temperature. Perhaps, under such excitations, the microstructure of the material deforms or undergoes though a metamorphosis process. We attempt to study the phenomena that take place within the finite domain of microstructure.
Material behavior of rubber seldom follows the classical elasticity theories. It is sensitive to rate of excitation and history. We attempt to predict the short term and long term behavior of rubbers under large deformation, high strain rate and consider geometric and material nonlinearities. What do you think about the other case, when the deformation is small, strain rate is small or the behaviors are linear? We attempt to write equations that are meant to express all such emotions of rubber. Perhaps these are the generalizations, away from the classical theories and the one can try to describe the simpler cases through simplifications of all such derivations. We consult the theories of continuum mechanics, thermodynamics, thermophysics and a bit chemistry as well. Our domain of consideration is a bit vast and wide.
The outcomes from such research do have applications in different field of engineering. In civil engineering, it is important to design the base isolation bearings for earthquake protection of bridges and buildings, traditional bridge bearings and tunnel linings. In the semiconductor industry, we need to design the seals and gaskets. These may be quite expensive as along as the adopted production technology is expensive. In aerospace and automotive industry, vibroacoustics issues need to be addressed adequately. In biomedical engineering, how do you think about the advantages of a shape memory polymer stent for treating the coronary heart disease? The constitutive equations working behind are the key to offer you a better performance.
Featured Papers:
- Nonlinear viscosity law in finite-element analysis of high damping rubber bearings and expansion joints
Amin, A. F. M. S., Bhuiyan, A. R., Hossain, T., & Okui, Y. (2014) - Application of rheology modeling to natural rubber and lead rubber bearings: A simplified model and low temperature behavior
Razzaq, M. K., Okui, Y., Bhuiyan, A. R., Amin, A., Mitamura, H., & Imai, T., (2012) - Effect of temperature history on the mechanical behaviour of a filler-reinforced NR/BR blend: Literature review and critical experiments
Amin, A.F.M.S., Lion, A., Hofer, P., (2010) - Nonlinear dependence of viscosity in modeling the rate-dependent response of natural and high damping rubbers in compression and shear: Experimental identification and numerical verification
Amin, A.F.M.S., Lion, A., Sekita, S., Okui, Y., (2006a) - Hyperelasticity model for finite element analysis of natural and high damping rubbers in compression and shear
Amin, A.F.M.S., Wiraguna, S.I., Bhuiyan, A.R., Okui, Y. (2006b) - Measurement of lateral deformation in natural and high damping rubbers in large deformation uniaxial tests
Amin, A.F.M.S., Alam, M.S., Okui, Y. (2003) - An improved hyperelasticity relation in modeling viscoelasticity response of natural and high damping rubbers in compression: Experiments, parameter identification and numerical verification
Amin, A.F.M.S., Alam, M.S. and Okui, Y. (2002)
