What process is used to improve the mechanical properties of sheet metal after forming?

The process used to improve the mechanical properties of sheet metal after forming is annealing. Annealing involves heating the metal to a specific temperature and then allowing it to cool slowly. This process helps to relieve internal stresses that develop during the forming process and results in improved ductility and toughness of the metal.

During annealing, the microstructure of the metal can change, often leading to a reduction in hardness and an increase in malleability. This makes the material easier to work with in subsequent fabrication processes. Hence, annealing is a widely used treatment in metalworking to enhance the properties of materials after they have undergone processes such as bending, stamping, or deformation.

The other processes mentioned, such as quenching, hardening, and tempering, are typically associated with other types of metallurgical treatments and can lead to different outcomes regarding hardness and brittleness, which may not be suitable for all formed sheet metal applications.