MATERIALS ENGINEERING – DAY 8
Review of Cold Work and Annealing
 Demonstration
 Metal Processing Examples

REVIEW QUESTIONS

What is cold work (CW) and how is it used in
metal processing?
What is annealing and how is it used in metal
processing?
 Name three phenomena associated with the
annealing process. Describe what happens to the
Cold Worked metal as each occurs.

SAMPLE COLD WORK CALCULATION

Can you calculate the cold work associated with
cold rolling a 0.25 inch thick plate down to a
thickness of 0.15 inches?
EXAMPLE PROBLEM – BASED ON FIGURE
7.19
A copper wire must be drawn to a diameter of 1/8 inches. We
are starting with stock having diameter of 1.0 inches. The
wire’s final %EL ductility must be greater than 20%. The
yield strength must exceed 30 ksi. Describe the processing
of this wire. (Maybe multiple steps?)
EXAMPLE PROBLEM – BASED ON FIGURE
7.19 – FINAL STEP OF CW
Observe that 10% < %CW < 16%. Settle on 13%. Calculate the
diameter at the start of the final step.
EXERCISE CONTINUED.
diameter
0.125
0.13401
0.17751
0.25103
0.35501
0.50206
0.71002
0.99423
13
43
50
50
50
50
49
We can see that a
number of steps of
cold work followed
by annealing must
be carried out.
The %CW is
arbitrary excep in
the last step, in
which we have to go
with 13% CW