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Leveling of Aged Low Carbon Steel Sheets in order to Prevent Shape Defects after Stamping

시효 발생한 저탄소 냉연강판의 가공형상 불량 방지를 위한 판재 교정기술 활용

  • Received : 2015.01.19
  • Accepted : 2015.05.06
  • Published : 2015.08.01

Abstract

In order to prevent shape defects such as fluting and stretcher strains during press forming of aged low carbon steel sheets, roller leveling conditions for reducing yield point elongation were studied. Yield point elongations of leveled sheets were determined as a function of leveling, which is defined as the plastic fraction or the ratio of plastically deformed part in sheet thickness section to the whole thickness of the sheet. By adjusting this plastic fraction during leveling to more than 78%, yield point elongation in the leveled sheets was reduced so no fluting occurred during subsequent tangential bending. Stretcher strains can be avoided by leveling the sheet to an 84% plastic fraction condition.

Keywords

Aging;Fluting;Stretcher Strain;Bending;Stamping;Leveling;Roller Leveler;Shape Defect

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