The utility model relates to a titanium billet (1) for hot rolling, which has: titanium cast billet (3); And a titanium plate (4) welded to a titanium billet (3) equivalent to the rolling surface (3A), a titanium billet (3) and the titanium plate (4) have the same chemical composition. Titanium billet for hot rolling (1) The surface properties of hot rolling can be maintained well even if the blank opening and refining processes are omitted.
Titanium material is generally manufactured as follows: the ingot obtained from the smelting process is made into a slab or billet shape in the opening process, and the surface is finished and then hot rolled, and then the implementation of annealing, cold processing and manufacturing.
In addition to the widely used VAR (Vacuum Arc Remelting) method, there are also EBR (Electron Beam Remelting) method and plasma Arc melting method, which are melted in different places and injected into the mold.
For the former, the mold is limited to the cylinder, so the plate manufacturing process requires a blank or forging process. In contrast, for the latter, the mold shape has a high degree of freedom, and a square mold can be used in addition to a cylindrical mold. Therefore, if the use of electron beam melting method, plasma arc melting method, you can directly cast square ingot, cylindrical ingot. Therefore, in the case of plate manufacturing from square ingot and bar and wire manufacturing from cylindrical ingot, the opening process or forging process can be omitted in the shape of the ingot, and the cost and time required by the opening process can be reduced. Therefore, the production efficiency can be expected to be significantly improved.
However, the casting structure of large ingot used in industry has coarse grains up to tens of mm in diameter. If such ingot is hot rolled directly without the opening process, surface defects will occur due to the influence of the deformation anisotropy between grains derived from the coarse grains.
