The beneficial effect of B on the hot ductility of 20CrMnTi steel with 0.05% Sn was
investigated. The results show that there is a trough in the hot ductility-temperature
curve. With the increase in the B content, the trough shifts to a lower temperature and
becomes shallow, and the hot brittle range becomes narrow. In addition, B greatly
enhancing the hot ductility was due mainly to its suppressing the Sn segregation,
retarding the austenite/ferrite deformation, accelerating the onset of dynamic
recrystallization (DRX) and promoting the intragranular nucleation of ferrite. Moreover,
in the present case, adding 92 ppm B can nucleation of ferrite. Moreover, in the present
case, adding 92 ppm B can obtain the best effect in improving the hot ductility of
20CrMnTi steel with 0.05% Sn.