METAL FORMING

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METAL FORMING
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LOCAL INSTABILITY IN TENSION TESTING OF THIN
SHEETS
In localized neck region, the strain along the
neck direction (2') is zero (plane strain
condition).
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SHEET METAL FORMING
Localized necking can give instability strain of
'2n', versus a value of 'n' is simple tension.
In practice, a diffuse neck (simple tension) is
followed by formation of localized necking. The
localized necking strain is influenced by sheet
anisotropy.
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ANISOTROPIC FACTOR, R
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SHEET METAL FORMING
Outer fibr strain, e (t/2)/(Rt/2)1/(2R/t)1
Minimum bend radius, specified as R/t ratios.
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SPRINGBACK
Note the effects of E and Y
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NEGATIVE SPRINGBACK
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ELIMINATING SPRINGBACK
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CRACKING AND FIBERING EFFECTS
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LENGTH OF BEND (OR WIDTH) EFFECT
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VARIOUS BENDING OPERATIONS
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BEND FORMING OPERATIONS
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TUBE BENDING
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ROLL FORMING
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STRETCH FORMING
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SUPERPLASTIC FORMING
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BENDING OF A CHANNEL
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MAKING SPECIAL BENDS AND SEAMS
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RUBBER FORMING
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BULGE FORMING
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EXPLOSIVE FORMING
Closely related is Electro-Hydraulic forming
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TUBE HYDROFORMING
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DEEP DRAWING
LDR affected by anisotropy.
Limiting Drawing Ratio LDR Do/Dp Ln (LDR)
Ln (Do/Dp) Drawing Stress/Y
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DEEP DRAWING
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ANISOTROPIC FACTOR, R
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EFFECT OF ANISOTROPY FACTOR
With anisotropy,
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EARING
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Ironing
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REDRAWING OPERATIONS
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DEEP DRAWING WITHOUT BLANK HOLDER
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TWO-PIECE BEVERAGE CAN MANUFACTURING
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FORMABILITY MEASUREMENTS
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FORMABILITY MEASUREMENTS
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FORMABILITY DIAGRAM
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FORMABILITY MEASUREMENTS
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DIFFERENT STATES OF STRAINS IN CAR BODY OPERATION
Denting Resistance