It has been suggested that deep drawability can be increased by (a) heating the flange and/or (b) chilling the punch by some suitable means. Comment on how these methods could improve drawability. Refering to Fig. 7.50, we note that:
(a) heating the flange will lower the strength of the flange and it will take less energy
to deform element A in the figure, thus it will require less punch force. This will reduce
the tendency for cup failure and thus improve deep drawability. (b) chilling the punch will increase the strength of the cup wall, hence the tendency for cup failure by the longitudinal tensile stress on element B will be less, and
deep drawability will be improved.