5. Conclusions

Heat treatments for metal alloys have become much more diversified since they were first developed for steel parts, either to facilitate forming operations or to harden the final product. They now contribute to enhancing the value of certain grades by adapting the micrographic structure to the main stages in a part's manufacturing process, and then to its properties of use. These application structures may concern the entire part, or be localized to functional surfaces (the teeth of a gear, for example), with a view to reducing costs or simplifying production routines and flows for mass-produced parts.

The main variants of industrial treatments cover: homogenization treatments, restoration-recrystallization annealing, grain softening or regeneration annealing, quenching and tempering, structural hardening aging and thermochemical treatments. These treatments are...