1Central Research and Development Laboratory, Kobe Steel Ltd., Kobe
Strain rate cycling tests have been performed during the tensile deformation in the temperature range 203°∼300°K of polycrystalline iron specimens aged at 200°C, aged at 200°C after straining at room temperature and strained at 200°C to study the influence of strain rate on the flow stress of aged iron. It has been found that the change in flow stress Δ σA associated with a 10:1 change in the strain rate tends to decrease with increasing strain and that the work hardening coefficient does not depend on temperature. The work hardening coefficient of aged iron is smaller than that of iron which is not aged. It is supposed that this decrease is due to the fact that the effective stress of the aged iron mainly decreases with increasing strain, although the effective stress of the unaged iron scarecely depends on the strain.
Please do not copy without permission.