25.520Level 5
Heat treatment of metals
Explanatory note
This class includes:
- general activities for the heat treatment of metals
- thermomechanical heat treatment of metals (e.g. preheating, annealing, hardening, tempering, quenching, deep freezing of metal)
- thermochemical heat treatment of metals (e.g. carburising, carbonitriding, nitrocarburising, nitriding, oxidising, sulphidising, boriding)