Review of Research on Titanium Oxides in Low‐Carbon Steel

Titanium oxides, which act as nuclei for intragranular ferrite (IGF), are common inclusions in low‐carbon steel. The interlocking structure of IGF greatly improves the mechanical properties of low‐carbon steel. To make the best use of this kind of oxide, the types, sizes, and distribution properties of effective titanium oxides are reviewed that can promote IGF nucleation. The control techniques of titanium oxides are summarized as follows: (1) Ti 2 O 3 is one of the most effective of the common titanium oxides, followed by TiO and TiO 2 . The type of titanium oxide can be affected by controlling the Ti/O mass ratio in molten steel. (2) Titanium oxide with a size range of 0.4–4 μm can effectively promote the nucleation of IGF or intragranular acicular ferrite (IAF), among them, titanium oxide of about 1 μm is the most beneficial to IAF nucleation. (3) To obtain titanium oxides with effective size, the precipitation of titanium oxides should be controlled during the solidification process, and this process can be achieved with the existing rapid solidification technology. Under the same conditions, the higher solidification rate can obtain finer titanium oxide.