Methods For Shaping Metals » Stretch-forming
Stretch-Forming
This is a technique used for shaping sheet metal over a stretch-block or former. The sheet metal is firmly gripped by clamps and the sheet is then stretched over the former by moving the clamps or the former. And the material is stretched beyond its elastic limit so that permanent deformation occurs.
This process is convenient for small batches of material but, local changes of form (concave/convex or vice versa) cannot be produced by this process.