A study of materials subjected to reductions in area by two-die swaging shows that non-uniform hardening occurs. The amount of cold work strengthening on the surface is the same as that for a similar reduction in area by cold rolling. The center hardness, however, is significantly greater. Cracks at the center of specimens are frequently observed. These effects are attributed to redundant working since successive blows strike new areas around the periphery but every blow affects the center.

This content is only available via PDF.
You do not currently have access to this content.