Page 45 - Module DMV20173
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3.0 SHEET METAL PROCESSES
Figure 3.15 Examples of various bending operations.
3.3.1 CONSIDERATIONS IN BENDING
a. Springback
1. Because all materials have a finite modulus of elasticity, plastic deformation
always is followed by some elastic recovery when the load is removed.
2. In bending, this recovery is called springback, which can be observed easily
by bending and then releasing a piece of sheet metal or wire.
3. Fig. 3.16 shows the springback in bending. The part tends to recover
elastically after bending, and its bend radius becomes larger. Under certain
conditions, it is possible for the final bend angle to be smaller than the original
angle (negative springback).
4. Fig. 3.17 shows the methods of reducing or eliminating springback in bending
operations.
5. Springback in forming operations usually is compensated for by overbending
the part.
BPLK 77 DMV 20173
