Forging

Thus we can approximate Eq.19 as
and Eq.21 becomes
p
σ
y
' ⎡
= σ
o ⎢
1+
⎣
_ a '
o ⎡ 2
=
∫
0
σ
a
⎢
1+
⎣
2µ
µ
( a − x)
h
⎤
⎥
⎦
( a − x) dx
h
⎥ ⎦
⎤
….Eq. 23
….Eq. 24
Integrating this gives:
_ '
o 2
p
2
σ ⎡ µ ax µ x ⎤
= ⎢x
+ −
….Eq. 25
⎥
a ⎣ h h ⎦
So that the average axial tooling pressure, p, is
a
0
_
p
⎛ =
' µ a
σ
o ⎜1
+
⎝ h
⎞
⎟
⎠
….Eq. 26
We can see that as the ratio a/h increases, the forming pressure p and
hence the forming load rises rapidly.
Suranaree University of Technology Tapany Udomphol
Jan-Mar 2007