Deformation friction induced

The deforming forces which induce flow in fluids are not recovered when these forces are removed. These forces impart kinetic energy to the fluid, an energy which is dissipated within the fluid. This is the origin of the idea that viscosity represents an internal friction which resists flow. This friction originates from the way molecules of the sample interact during flow. 

As reviewed thermoplastics (TPs) being viscoelastic materials respond to induced stress by two mechanisms viscous flow and elastic deformation. Viscous flow ultimately dissipates the applied mechanical energy as frictional heat and results in permanent material deformation. Elastic deformation stores the applied mechanical energy as completely recoverable material deformation. The extent to which one or the other of these mechanisms dominates the overall response of the material is determined by the temperature and by the duration and magnitude of the stress or strain. The higher the temperature, the most freedom of movement of the individual plastic molecules that comprise the... 

Whereas the discussion of crushing strength of cellular polymer material may not be very relevant to CMP pads, the surface deformations induced by the frictional shear forces argue for a discussion of the tensile fracture... 

Friction between the dowel and the substrate during insertion by high-speed rotation causes temperature-induced lignin softening and deformation and wood weld-... 

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