Optimization of temperature and rate regimes of plastic deformation by the criterion of dissipation of mechanical energy

Conclusions

• 1. The approaches of nonequilibrium thermodynamics allow us to formulate a new criterion for optimizing the choice of the temperature and rate of plastic deformation for structural steels and alloys. This is the fraction η of the energy supplie to the material which is spent for accommodation adjustments of the material in the process plastic deformation.

• 2. By plotting three-dimensional diagrams and contour maps of constant values of η in the coordinates$\dot \varepsilon - t$, we can localize the temperature and rate ranges of maximum values of η.

• 3. A study of the structure and phase composition has shown that the maxima of the efficiency of energy dissipation usually correspond to the simultaneous occurrence of accommodation processes such as dynamic recrystallization, grain-boundary slip, and phase recrystallization.

• 4. The use of the new criterion makes it possible to create a simple and effective algorithm for choosing optimum tempeature and rate regimes for plastic deformation of structural materials.