5. Forming processes

The forming processes used for superplastic materials can be classified into two broad categories:

• processes derived from those used for plastics, such as thermoforming and blow moulding;

• conventional metal and alloy deformation processes such as forging, and powder metallurgy combined with forging for nickel-based superalloys in particular.

In this section, only the first category is briefly discussed, due to its unusual nature for metallic materials, on the one hand, and its importance for aluminum and titanium alloys, which make up the bulk of applications, on the other.