1. EXPERIMENT # 8 Instructor: M.Yaqub
COLD WORKING
EXPERIMENT # 8
Instructor: M.Yaqub

2. COLD WORKING
Cold working is the plastic or permanent deformation at room temperature. In this process, volume remains same.
Shape of the metals are changed by using cold working process.
After cold working process, hardness and strength of the metal increases due to increase in dislocation density.

3. COLD WORKING PROCESS
Cold Rolling and wire drawing are the examples of cold working process.

4. % COLD WORK
The % cold work is defined as
And also can be expressed as

5. % COLD WORK (Continue) Where A0 is the original area of cross section
Ad is the area after deformation
e is the strain.

6. EFFECT OF CW ON TENSILE STRENGTH

7. EFFECT OF CW ON YIELD STRENGTH

8. EFFECT OF CW ON DUCTILITY

9. LAB REPORT
Complete the Table provided to you in lab. Use excel for calculation and attach a print out with the lab report.
Draw a graph hardness vs %CW cumulative using excel, hardness on Y-axis and %CW cumulative on X-axis. Named it as Figure 1.

10. LAB REPORT (Continue)
Draw another graph hardness vs %True strain cumulative using excel, hardness on Y-axis and True strain cumulative on X-axis. Named it as Figure 2.
Include the cover page in your lab report.