Many metal-forming processes involve plastic deformation at medium or high rates of strain. In most such processes the material is subjected to a complex stress and strain history as it is deformed, and it is therefore difficult to determine precisely the strain rates involved. However, estimates of the orders of magnitude of these rates may be obtained by making reasonable assumptions concerning the kinematics of deformation. Atkins  has derived the following values for typical dimensions and speeds of working: sheet, rod or wire drawing, 1−103s−1; cold rolling, 102−103s−1; deep drawing, 1s−1. Green and Maiden  have estimated that strain rates in deep drawing may be as high as 102s−1.
KeywordsFlow Stress Mild Steel Plastic Zone Deep Drawing Strain History
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