3. Hot forming

Hot-working processes include rolling, forging, and die-forging. Of all these processes, rolling is by far the most important, as it accounts for the vast majority of the tonnage produced.

Compared to carbon steels, the following specific points must be taken into account during the hot working of stainless steels:

• Because their thermal conductivity is lower, a significantly longer heating time is required to achieve uniform temperatures (approximately 3 hours for 200-mm-thick austenitic stainless steel slabs);

• Since their mechanical properties at elevated temperatures are higher, the mechanical forces required to process them are also higher;

• The inability to refine the grain through heat treatment in ferritic and austenitic grades requires strict...