A supersaturated solid solution soft magnetic material and a preparation method thereof are provided, belonging to the field of metal soft magnetic technologies. The supersaturated solid solution soft magnetic material is soft magnetic alloy with proportions of 72.0˜78.0 at % Fe, 12.0˜18.0 at % Si, 4.0˜12.0 at % Co and 1.0˜3.0 at % Ti. The preparation method uses molten glass purification or electromagnetic levitation melting to an alloy melt with a target supercooling degree, increases the solid solubility of the Ti element in α-Fe (Si, Co), and promotes the formation of supersaturated solid solution of Ti, thereby achieving the goal that the magnetocrystalline anisotropy constant and the magnetostriction coefficient tend to be zero. Ti element is uniformly distributed in the α-Fe (Si, Co) after supercooled solidification analyzed by X-ray energy spectrometer, a supersaturated solid solution alloy without Ti precipitation is obtained, and the soft magnetic alloy has low coercivity and high permeability.

A cored wire for refining molten metal includes a reactive core material that is in the form of a solid rod. A non-reactive particulate material radially surrounds the solid core material, and an exterior metal jacket radially surrounds the particulate material. The particulate material may include wood or other material that when introduced into the molten metal, undergoes thermal decomposition to release carbon dioxide, hydrocarbons, or combinations thereof as a shroud around the core material.

A cored wire for refining molten metal includes a reactive core material that is in the form of a solid rod. A non-reactive particulate material radially surrounds the solid core material, and an exterior metal jacket radially surrounds the particulate material. The particulate material may include wood or other material that when introduced into the molten metal, undergoes thermal decomposition to release carbon dioxide, hydrocarbons, or combinations thereof as a shroud around the core material.

A ferritic stainless steel with chemical composition includes, in mass %, Cr: 10.5 to 25.0%; Al: 0.01 to 0.20%; Ti: 0.15% to 0.35%; O: 0.0001 to 0.0030%; and Mg: 0.008×[% Al] or more, in which oxysulfide-containing inclusions are present in the steel, a number ratio of the oxysulfide-containing inclusions whose minor axis is 3 μm or more is 5 pieces/mm.sup.2 or less, and a number ratio of the oxysulfide-containing inclusions whose minor axis is 15 μm or more is 0.05 pieces/mm.sup.2 or less. 75% or more of the inclusions whose minor axis is 3 μm or more have an oxysulfide part whose composition satisfies formulae (1) and (2),

CaO+Al.sub.2O.sub.3+MgO≥90%  formula (1),

Al.sub.2O.sub.3/MgO≤1.25  formula (2).

A steel consists of, in mass %, C: 0.25 to 0.45%, Si: 0.10 to 0.50%, Mn: 0.40 to 0.70%, P: 0.015% or less, S: 0.005% or less, Cr: 0.80 to 1.50%, Mo: 0.17 to 0.30%, V: 0.24 to 0.40%, Al: 0.005 to 0.100%, N: 0.0300% or less, O: 0.0015% or less, and the balance being Fe and impurities, and satisfies Formula (1) to Formula (4) described in the present specification, wherein: its microstructure is composed of ferrite and pearlite having a total area fraction of 5.0 to 100.0%, and a hard phase having a total area fraction of 0 to 95.0%; a proportion of a total area of CaO—CaS—MgO—Al.sub.2O.sub.3 composite oxides with respect to a total area of oxides in the steel is 30.0% or more; and a number density of oxides having an equivalent circle diameter of 20.0 μm or more is 15.0 pieces/mm.sup.2 or less.

A Si-killed steel wire rod for obtaining a spring excellent in fatigue properties and a spring excellent in fatigue properties obtained from such steel wire rod are provided. In the Si-killed steel wire rod of the present invention, oxide-based inclusions present in the wire rod contain SiO.sub.2: 30-90%, Al.sub.2O.sub.3: 2-35%, MgO: 35% or below (not inclusive of 0%), CaO: 50% or below (not inclusive of 0%), MnO: 20% or below (not inclusive of 0%) and BaO: 0.2-20% respectively, and total content of (CaO+MgO) is 3% or above.

A Si-killed steel wire rod for obtaining a spring excellent in fatigue properties and a spring excellent in fatigue properties obtained from such steel wire rod are provided. In the Si-killed steel wire rod of the present invention, oxide-based inclusions present in the wire rod contain SiO.sub.2: 30-90%, Al.sub.2O.sub.3: 2-35%, MgO: 35% or below (not inclusive of 0%), CaO: 50% or below (not inclusive of 0%), MnO: 20% or below (not inclusive of 0%) and BaO: 0.2-20% respectively, and total content of (CaO+MgO) is 3% or above.

A method of casting a steel semi-product from a liquid steel, the steel semi-product having a targeted composition in titanium of at least 3.5% in weight.

A control process of inclusions in ultra-clean rare earth steel, wherein the content of rare earth elements REM in the ultra-clean rare earth steel, the total oxygen content T[O]m, the total sulfur content T[S]m in the steel, and the total oxygen content T[O]r in a rare earth metal or alloy added to the steel are controlled to satisfy the following formula: −500<REM−(m*T[O]m+n*T[O]r+k*T[S]m)<−30, where REM is the content of rare earth elements in the steel, in ppm; T[O]m is the total oxygen content in the steel, in ppm; T[O]r is the total oxygen content in a rare earth metal or alloy added to the steel, in ppm; T[S]m is the total sulfur content in the steel, in ppm; m is a first correction coefficient, with a value of 2-4.5;n is a second correction coefficient; and k is a third correction coefficient.

A control process of inclusions in ultra-clean rare earth steel, wherein the content of rare earth elements REM in the ultra-clean rare earth steel, the total oxygen content T[O]m, the total sulfur content T[S]m in the steel, and the total oxygen content T[O]r in a rare earth metal or alloy added to the steel are controlled to satisfy the following formula: −500<REM−(m*T[O]m+n*T[O]r+k*T[S]m)<−30, where REM is the content of rare earth elements in the steel, in ppm; T[O]m is the total oxygen content in the steel, in ppm; T[O]r is the total oxygen content in a rare earth metal or alloy added to the steel, in ppm; T[S]m is the total sulfur content in the steel, in ppm; m is a first correction coefficient, with a value of 2-4.5;n is a second correction coefficient; and k is a third correction coefficient.