Dissipated plastic energy

True vs. apparent strength the visco-plastic energy dissipation dominated the magnitude of the peel strength. However, little dissipation occurs if the interface becomes very weak. In other words, some influxes are necessary to produce sufficient stress to activate the viscoelastic deformation in the body of the A. 

A second major difficulty with the Peierls model is that it is elastic and therefore conservative (of energy). However, dislocation motion is nonconservative. As dislocations move they dissipate energy. It has been known for centuries that plastic deformation dissipates plastic work, and more recently observations of individual dislocations has shown that they move in a viscous (dissipative) fashion. 

Plastic energy dissipation and frictional energy dissipation, in that order of importance, where compacted polymer particulates are relentlessly deformed by twin rotor devices, which rapidly raise their temperature and create regions of melts. 

On the other hand, we discussed and presented in physical terms the very powerful melting mechanisms resulting from repeated, large deformations, forced on compacted particulate assemblies by twin co- or counterrotating devices. These mechanisms, which we refer to in Section 5.1, are frictional energy dissipation (FED), plastic energy dissipation (PED), and dissipative mix-melting (DMM). 

Fig. 10.60 Compressive stress-strain behavior of PS and LLDPE at 25°C and crosshead speed of 25.4 mm/min. At a compressive stress level of 20 MPa the deformation of the soft LLDPE is large, in the dissipative region and nearly twenty times the PS deformation, which is of the order of 0.04, in the elastic nondissipative range. [Reprinted by permission from B. Qian, D. B. Todd, and C. G. Gogos, Plastic Energy Dissipation (PED) and its Role in Heating/Melting of Single Component Polymers and Multi-component Polymer Blends, Adv. Polym. Techn., 22, 85-95 (2003).]...

B. Qian, D. B. Todd, and C. G. Gogos, Plastic Energy Dissipation and its Role on Heating/ Melting of Single-component Polymers and Multi-component Polymer Blends, Adv. Polym. Technol., 22, 85-95 (2003). 

B. Qian and C. G. Gogos, The Importance of Plastic Energy Dissipation (PED) to the Heating and Melting of Polymer Particulates in Intermeshing Co-rotating Twin Screw Extruders, Adv. Polym. Tech., 19, 287-299 (2000). 

C. G. Gogos and B. Qian, Plastic Energy Dissipation during Compressive Deformation of Individual Polymer Pellets and Polymer Particulate Assemblies, Adv. Polym. Tech., 21, 287-298 (2002). 

This type of friction is most important in cyclic processes like rolling friction and automobile tires. Mechanical damping and delayed recovery cause dissipation of energy consequently, rolling friction and mechanical damping are well correlated. For a hard ball rolling on a plastic surface the following expression was found by Flom (1961) ... 

Basu and Van der Giessen [9] extended the above isothermal formulation to account for thermal effects associated with the heat dissipated by plastic dissipation of the bulk and from the craze process. The plastic energy dissipation rate per unit volume is specified in Eq. 4, so that the energy balance inside the material can be written as... 

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