Hardness profile of AISI 444 steel after a stamping operation

ABSTRACT

The mechanical and microstructural characterization of stamped products is essential to identify defects and be a guide to improve the properties in general, amplifying the range of applications for different types of materials. In this context, the study of the relationship between the mechanical properties and the respective structural arrangement assumed by steel during a stamping operation is a valuable method for control of quality, as well as for assessing the occurrence of failures such as the development of an inadequate crystallographic orientation for a stamped product and the identification of regions that experienced intense mechanical efforts and plastic deformation, considered critical to a possible sheet thinning. This work executes the mechanical evaluation of AISI 444 ferritic stainless cup, with the description of Vickers hardness profile in different positions, combined with the corresponding microstructural aspects in the same positions of the mechanical investigation. Considering that all experimental procedures were conducted under cold working, the microstructural analysis exhibited reduced grain orientation, even in the regions that experienced a higher amount of plastic deformation and work-hardening and, consequently, higher Vickers hardness. It detected a higher variability of mechanical resistance than modifications in the microstructural aspects of AISI 444 ferritic stainless steel.

Keywords:
Hardness profile; Stamping; AISI 444 steel; Microstructural characterization