抄録
It has been experimentally said that the drawability is better for the coarse-grained material. But it is doubtful that this principle can be applied to all cases. This principle can be applied to the case if the flow stress is higher for fine-grained material at low strains, and after sufficient strain the mechanical properties become the same for both fine and coarse grains. But this principle can not be applied if the flow stress at low and high strains is lower for coarse-grained material than fine-grained material. On the other hand, the component of directionality is a good indicator of drawability. So the drawability is also considered in terms of directionality. From these points of view, the investigations were done with 70-30 brass, 18-8 stainless and mild steel.
The drawability of 70-30 brass and 18-8 stainless, which have face centered cubic lattice, is dependent upon the grain size, while that of mild steel, which has body centered cubic lattice, is dependent upon the directionality rather than the grain size.
