Elastic modulus is the characterization of the parameters of the mechanical properties of solid materials, and the viscosity is liquidity qualitative characterization of fluid parameters. In order to understand the physical meaning of viscosity of rubber joint material, should first study and distinguish the type of rubber joint material deformation.
Polymer (the main material of rubber joint - rubber) for material processing and use of the material deformation type, main should study material deformation and stress, the relationship between deformation and stress size change over time., according to the relationship between these two kinds of materials can be divided into elastomeric, liquid and plastic body and viscoelastic body, four of its characteristics such as described below.
1. The elastomers including projectile and high projectile. Except their common characteristic is the force deformation can reply, after all the difference in with the deformation of time dependencies, elastic deformation has nothing to do with the time, timely development and recovery; High elastic deformation is gradually developed over time, deformation recovery also need some time.
2. The liquid flow is one of the important characteristics of ordinary liquid in less under the action of external force can generate large deformation. The liquid have absolute liquidity, there is no flow limit stress. But in the bottom in a timely manner is very small under the action of external force, also can produce certain deformation rate. The ratio of stress and deformation rate is constant; obey Newton's law of viscous flow of Newtonian fluid. The ratio of stress and deformation rate is not constant; neither obeys Newton's law of viscous flow of non-Newtonian fluid.
3. Plastic body under the action of external force can flow, and generate irreversible deformation, but different from liquid, it does not have absolute liquidity, namely can't flow and deformation in the external force is small, only if the stress reaches or checked after the yield stress to flow. So the plastic body may be defined as a flow of current yield value.
4. The viscoelastic body and plastic projectile with viscoelastic non-Newtonian fluid and viscoelastic body with plastic. This kind of material is a combination of non-Newtonian fluid, high plastic body and the characteristics of the projectile, the deformation in a more complex process. Mixing rubber and rubber, most of the other high polymer materials belong to this category. Only under the extremely slow processing speed, some flow properties of the rubber is close to Newton fluid or plastic body, say again so fake plastic body.
