Abstract: A titanium slab is appropriate for hot rolling, is produced by electron beam melting furnace, has superior linearity so that it can be fed into a hot rolling machine without performing breaking down process or other subsequent correcting process after production, and has good structure having no cracks at the corner parts. A process for production thereof is also provided. The titanium slab is directly produced by a mold of an electron beam melting furnace, and has the deformation of not more than 5 mm for the thickness direction versus the longitudinal direction and deformation of not more than 2.5 mm for the width direction versus the longitudinal direction, both per a length of 1000 mm of the slab. The process for production of this titanium slab for hot rolling has a step of using an electron beam melting furnace in which its rectangular mold has mold walls of a long side and mold walls of a short side, and a step of pouring molten metal from one of the mold walls of a short side.

Abstract: The present invention provides a titanium slab for hot rolling which can be fed into a general purpose hot-rolling mill for producing strip coil, without passage through a breakdown process such as blooming or a straightening process, and can further suppress surface defect occurrence of the hot-rolled strip coil, and a method of producing and a method of rolling the same, characterized in that in the cast titanium slab an angle ? formed by the crystal growth direction (solidification direction) from the surface layer toward the interior and a direction parallel to the slab casting direction (longitudinal direction) is 45 to 90°, and moreover, there is a surface layer structure of 10 mm or greater whose ? is 70 to 90°, and further characterized in that a crystal grain layer of 10 mm or greater is formed whose C-axis direction inclination of a titanium ? phase is, as viewed from the side of the slab to be hot rolled, in the range of 35 to 90° from the normal direction of the surface to be hot rolled.

Abstract: The present invention provides a titanium material for hot rolling which enables reduction of defects on the surface (in the case of a flat material or strip coil, including not only the flat surfaces but also the side surfaces and edges) due to hot rolling. The titanium material for hot rolling has dimples imparted by cold plastic deformation whose mean value of the heights (Wc) of the undulation profile elements is 0.2 to 1.5 mm and mean value of the lengths (WSm) thereof is 3 to 15 mm. The invention also provides a method of producing the titanium material and a method of hot rolling the titanium material.

Abstract: The present invention provides a titanium material for hot rolling that enables reduction of defects occurring on the surface (in the case of a flat material or strip coil, including not only the flat surfaces but also the side surfaces and edges) owing to the hot rolling, and a method of producing the same, particularly to a titanium material for hot rolling enabling omission of an ingot breakdown process, and a method of producing the same, characterized in that it is a titanium material for hot rolling having dimples imparted by cold plastic deformation whose mean value of the heights (Wc) of the undulation profile elements is 0.2 to 1.5 mm and mean value of the lengths (WSm) thereof is 3 to 15 mm, and makes it possible to minimize surface defects occurring in hot rolling even if a process for breaking down the ingot is omitted.

Abstract: An apparatus and method allows the width of high-melting temperature reactive metallic slabs produced in an electron beam melting furnace to be easily changed. The apparatus for production of the metallic slabs by the electron beam melting has a metal melting part and a metal extraction part mutually separated by an air tight valve; a metal melting part has a melting chamber, electron gun, hearth, a mold of variable wall distance, and an air tight valve; and the metal extraction part has a slab chamber, an extraction base, an extracting shaft, and an drive unit for extracting the metal slab. The method for production of the metallic slab using this apparatus has a step of pulling a previous metallic slab produced in the rectangular mold out of the rectangular mold, a step of moving the short mold wall(s) of the rectangular mold to change the width of the rectangular mold, and a step of producing a subsequent metallic slab.

Abstract: The present invention provides a titanium slab for hot rolling which can be fed into a general purpose hot-rolling mill for producing strip coil, without passage through a breakdown process such as blooming or a straightening process, and can further suppress surface defect occurrence of the hot-rolled strip coil, and a method of producing and a method of rolling the same, characterized in that in the cast titanium slab an angle ? formed by the crystal growth direction (solidification direction) from the surface layer toward the interior and a direction parallel to the slab casting direction (longitudinal direction) is 45 to 90°, and moreover, there is a surface layer structure of 10 mm or greater whose ? is 70 to 90°, and further characterized in that a crystal grain layer of 10 mm or greater is formed whose C-axis direction inclination of a titanium a phase is, as viewed from the side of the slab to be hot rolled, in the range of 35 to 90° from the normal direction of the surface to be hot rolled.

Abstract: A titanium slab is appropriate for hot rolling, is produced by electron beam melting furnace, has superior linearity so that it can be fed into a hot rolling machine without performing breaking down process or other subsequent correcting process after production, and has good structure having no cracks at the corner parts. A process for production thereof is also provided. The titanium slab is directly produced by a mold of an electron beam melting furnace, and has the deformation of not more than 5 mm for the thickness direction versus the longitudinal direction and deformation of not more than 2.5 mm for the width direction versus the longitudinal direction, both per a length of 1000 mm of the slab. The process for production of this titanium slab for hot rolling has a step of using an electron beam melting furnace in which its rectangular mold has mold walls of a long side and mold walls of a short side, and a step of pouring molten metal from one of the mold walls of a short side.

Abstract: Permanent waving composition containing as active ingredients cysteine and N-acetylcysteine. The composition contains preferably 3-15% cysteine and 0.2-3% N-acetylcysteine. It is possible to avoid the separation of crystals derived from the air-oxidation of cysteine by the composition of the present invention.