Measurement of Springback

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Measurement of Springback

• DP780 and TRIP780

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Draw-bend Test
25 mm, 50mm
25 in

• Yield Strength 450 MPa
• Tool radius 7/8 in.
• Thickness was measured at 10 random points
  and averaged. 1.5755mm (DP), 1.4535mm (TRIP)
• R/t 7.053 (DP), 7.645 (TRIP)
• Draw restraint (via back force) set at a fraction
  of materials yield strength 0.4, 0.6, 0.8,
  0.9, 1.0, 1.1

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Draw-bend Equipment
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Draw-bend Equipment with sample loaded
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Tested Specimen (w25mm)
DP780
TRIP780
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Tested Specimen (w50mm)
DP780
TRIP780
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Springback Angles (w25mm)
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Springback Angles (w50mm)