不活性気体
The material is first heated up to promote superplasticity. For titanium alloys e.g. Ti 6Al 4V and some stainless steels this is around and for aluminium alloys e.g. AA5083 it is between 450–520 °C. In this state the material becomes soft so processes that are usually used on plastics can be applied, such as: thermoforming, blow forming, and vacuum forming. Inert gas pressure is applied on the superplastic sheet forcing it into a female die.