For various projects metal does not necessarily need to be heated to be shaped. It is the case for easy shaping metal sheets, for unriveted chainmails, and pliable metals.
The rings of chainmails and hauberks are made out of a iron wire which is winded around a tube with a small diameter. Obtaining this way tight springs from which the rings are cut one by one with the help of pincers. The rings are then assembled using a pair of pliers allowing to open and close each ring. Therefore, 200 to 300 hours are required to complete a 40 000 rings hauberk.
Pieces of plate armor and jewels are eather shaped by hand pushing or hammering against a conter-shape. Both methods might be used for the same piece.
By working with a cool material, the metal becomes breakable under pressure. It is the strain hardening. To avoid splitting it just needs to be heated enough with a torch.