CAST TITANIUM SLAB FOR USE IN HOT ROLLING AND EXHIBITING EXCELLENT SURFACE PROPERTIES AFTER HOT ROLLING, EVEN WHEN OMITTING BLOOMING AND PURIFYING STEPS, AND METHOD FOR PRODUCING SAME

摘要

Provided is a titanium cast product for hot rolling made of commercial pure titanium or a titanium alloy, the titanium cast product including, in a surface serving as a rolling surface, a fine structure layer that is formed of an acicular structure formed in the outermost surface by melting and re-solidification treatment and that has a thickness of more than or equal to 5 mm and less than 9 mm in depth. In the titanium cast product for hot rolling according to the present invention, the surface is flat, the number of minute voids in the interior immediately below the surface is small, and the outermost surface has a significantly fine structure. When the titanium cast product is subjected to hot rolling, the occurrence of concavities on the surface in the early stage of hot rolling and the occurrence of surface defects on the hot rolled sheet can be stably prevented at a practical level.