Plasticity in casting - Hot metals

The objective of this section is to more realistically account for the behavior of metals at elevated temperatures, as described in the document [42]: the sensitivity of the plastic flow stress to strain rate and temperature.

Furthermore, it is important to account for thermal phenomena (energy transfer and dissipation) that influence the metal’s temperature, behavior, deformation, and stresses: rheology, expansion or contraction, and structural changes. Compared to the document [16], we will therefore discard assumptions 4 and 5 and assumption E∞.

You will find the table of notations and symbols at the end of this document.

Behavior during hot forming involves:

• formulation of viscoplastic behavior and friction during hot forming;

• calculation of the temperature field T and thermomechanical couplings;

• presentation of the principles of thermomechanical metallurgy for the analysis of deformation, the stress field, and the structure of the metal as it cools after hot forming—a problem similar to that of its behavior during heat treatments [79] and welding operations [80].