In the deep drawing process, multi-pass deep drawing was usually used to get larger limit drawing ratio when the fracture may occur by using the single pass deep drawing.
And we know that the key to determining whether the deep drawing can be completed in one pass is whether the unit pressure on the hazard section is less than the tensile strength of the material.When the unit pressure on the hazard section is greater than the tensile strength, the single pass deep drawing will lead to the fracture.
What happened when the single pass deep drawing changed to multi-pass deep drawing? What' the intrinsical difference?
