The hot ductility of Ti-bearing steel was studied by theoretical calculation and a
thermal simulation experiment. Meanwhile, microsegregation and precipitates were analyzed.
The results showed that the S, P and O elements were enriched at the grain boundaries,
while the hot ductility was deteriorated by inclusions of (Fe, Mn, Si, Al)(S,O) in the
interdendritic region. At a temperature of 1300 °C, large TiN particles have little effect
on the hot ductility. In the temperature range from 1000 °C to 900 °C, the Reduction of
Area (R.A) declined rapidly from 81.77%
to 31.77%, with the size of particles decreasing from 5 to 20 nm and quantity increasing
from 1.2 inds/μm2 to 354 inds/μm2,
respectively. In the temperature range from 900 °C to 850 °C,
R.A decreased from 31.77% to 30.12%
with the ferric films gradually thickening. The critical stress, 63.58 MPa, was equal to
tensile strength at 912 °C. Intergranular fracture occurred easily with higher critical
stress below 912 °C.