Taylor Castagna
MANE 6963 – Friction and Wear of Materials
Prob 3.
Copper
Assumed properties used were yield strength of 365 MPa and a linear tangent modulus of 552 MPa. The tangent
modulus will mimic a linear isotropic hardening
Reference: http://www.journalamme.org/papers_vol24_1/24127.pdf.
Figure 1 – Elastic
Figure 2 - Elastoplastic
With a constant displacement, the results show a decrease in stress between Figure 1 and Figure 2. This is due to the
change in rate of stress/strain once the material has reached the proportional limit. Unloading of the flat punch will
show a significant amount of permanent plastic strain.
Aluminum
Assumed properties used were yield strength of 55 MPa and a linear tangent modulus was estimated using Figure 3. The
rate of strain hardening for aluminum is particularly low.
Figure 3 – Tension Test of Aluminum
Taylor Castagna
MANE 6963 – Friction and Wear of Materials
Figure 4 – Elastic
Figure 5 – Elastoplastic
Due the low yield strength of aluminum and the high displacement (1e-3) used as an input in this simulation,
the surrounding material on the punch began yielding to an extreme extent before the punch reached its
maximum depth. The stress in Figure 5 is an entire factor smaller than the elastic model used in Figure 4. This is
due to the very low strain hardening rate of the aluminum.