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The main subject of this investigation concerns the change and improved drawability of type 304 stainless steel nonhomogeneous deformation temperature distribution. Type 304 stainless steel sheets of thickness 0.8 mm were deep-drawn by a working process in which a hot die and a cold punch were used. working temperature ranged from 25℃ to 150℃. The cylindrical square- shaped cup products subjected to microstructural examination with a transmission electron microscope were In room- temperature performance, the sheet metal failed in cylindrical deep drawing because of severe work-hardening. As the temperature was raised and the punch was not cooled, it also led plastic instability due to its poor ductility and small rate of work hardening. The drawability was improved by nonhomogeneous deformation in the range 50~125℃ with a heated die and a cooled punch. This effect disappeared as the temperature was increased 150℃. The microstructures appearing under various working were investigated, and effects on drawability of steel sheets
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