Civil Engineering Reference
In-Depth Information
Fig. 4.12
Ti-G2 temperature
profiles. The temperature
profiles for a conventional
compression, EAF
compression, and stationary
electrical test are shown, with
single points representing
the maximum temperatures
of the stationary electrical
experiments at L
1
and L
2
Stationary,
L
0
- 300A
Stationary,
L
1
- 300A
Stationary,
L
2
- 300A
EAF - 300A
Conventional
compression
Fig. 4.13
Ti-G2 model
with EEC (L
0
-L
2
). The
EEC power law function
was optimized such that it
agreed with the experimental
temperature profile
EAF Model
EAF Test
300A
The same temperature model prediction process procedure was followed for
Ti-G5. The model and experimental results for the stationary electrical test are
shown in Fig.
4.14
. For this test, a specimen machined to L
2
dimensions was used
in the experiments. The model and experiments matched closer than for Ti-G2.
As was done for Ti-G2, an EEC function was developed to match the model
and experimental EAF thermal profiles, shown in Fig.
4.15
. For this material, the
model produced roughly the same peak temperature as the experiments, but the
model showed a slightly slower heating profile, as was also seen for Ti-G2.
Figure
4.16
displays the EEC profiles for an EAF test from L
0
-L
2
(0-12 s). Of
note is that the Ti-G5 profile ends at 6 s, while the Ti-G2 profile extends to 12 s.
This is because the Ti-G5 specimens failed after L
1
and were not able to be con-
ventionally formed to L
2
without fracture. The coefficients were found to be non-
linear and were approximated using the power law.
From Fig.
4.16
, the EEC for each Ti-grade is different, due to differences in the
electrical, thermal, and microstructure properties of the two materials. In particu-
lar, the Ti-G2 EEC increased rapidly in the first few seconds of deformation, hence
