Cutting applied as test method for acquisition of flow stress data at high strains and strain rates

In rapid metal forming processes, very high strain and strain rates are experienced. It is therefore important to determine the flow stress of metals under such conditions. In the cutting process, it is well known that high strains occur in a localized shear zone formed as the shearing punch penetrates down into the material to be cut. In rapid cutting, very high strain rates are also experienced in the shear zone. Cutting was therefore investigated to see if the process is suitable as technological test for acquisition of flow stress data for metals. It is shown how approximate RT flow stress data can be obtained in partial cutting tests if the flow stress of the sheet obeys the power-law.