2. Contact mechanics of polymers

2.1 Rheological properties of polymers

Figure 5 shows the stress σ - strain ε curves of various polymers: they generally comprise three parts:

• an initial phase of strongly increasing stress, corresponding to small elastic and viscoelastic deformations, which disappear rapidly after the specimen has been discharged; to a first approximation, this range is characterized by the slope of the curve, which can be identified with the Young's modulus E, whose value depends on the deformation imposed on the...