TSI axis is necessary only if cyclic stress values are need to be predicted cycle to
cycle. However, this mapping process is not needed if only final number of cycles to
failure is needed. System will degrade along TSI axis.
Φ cr ¼ 0:00545T þ 0:659 T 100
C
-80
-60
-40
-20
0
20
40
60
-0.010
-0.005
0.000
0.005
0.010
Strain
)
a
P
M
(
s
s
e
r
t
S
Test
Simulation
Fig. 6.27 Uniaxial stressstrain hysteresis loop from
simulation vs. experimental
data for cycle 104 at room
temperature with strain
amplitude of 0.6%
-40
-30
-20
-10
0
10
20
30
-0.009 -0.006 -0.003 0.000 0.003 0.006 0.009
Strain
)
a
P
M
(
s
s
e
r
t
S
Test
Simulation
Fig. 6.28 Uniaxial stressstrain hysteresis loop from
simulation vs. experimental
data for cycle 5 at 75
C
with strain amplitude of
0.6%
6.8 Verification Examples
339