Nippon Steel Corporation

Nippon Steel Sumitomo Metal Corporation

Nippon Steel Stainless Steel Corporation

Katsuhiro Fuchigami

Hiroyuki Kondo

Koichi Chiba

Eiichi Takeuchi

Ryuji Uemori

Takehiko Toh

Akihiro Ono

Kazushige Umezawa

Masamitsu Wakoh

Tokio Suzuki

Takashi Aramaki

Yuji Ogawa

Yoshiharu Inoue

Takashi Morohoshi

Kazuhisa Kusumi

Shigeru Kaneko

Hideaki Irikawa

Kohsuke Kume

Takahisa Honda

Akihiro Matsuzawa

There is provided a hot-stamped member or a steel sheet for hot stamping having a chemical composition including, in mass %, C: 0.25% or more and 0.55% or less, Si: 0.001% or more and 2.0% or less, Mn: 0.3% or more and 3.0% or less, P: 0.02% or less, S: 0.003% or less, Al: 0.005% or more and 1.0% or less, Cr: 0% or more and 1.0% or less, Mo: 0% or more and 1.0% or less, N: 0.02% or less, Ca: 0% or more and 0.0010% or less, B: 0.0005% or more and 0.01% or less, one or two or more selected from the group consisting of Ti: 0.005% or more and 0.5% or less, Nb: 0.005% or more and 0.5% or less, V: 0.005% or more and 0.5% or less, and Zr: 0.005% or more and 0.5% or less, and Ni+Cu+Sn: 0% or more and 2% or less, and a remainder consisting of Fe and impurities.

Hot-stamped member and steel sheet for hot stamping

Ferritic stainless steel securing corrosion resistance while being excellent in ridging resistance able to be stably provided, that is, ferritic stainless steel with excellent ridging resistance having a composition comprising, by mass %, C: 0.001 to 0.01%, Si: 0.3% or less, Mn: 0.3% or less, P: 0.04% or less, S: 0.01% or less, Cr: 10 to 21%, Al: 0.01 to 0.2%, Ti: 0.015 to 0.3%, O: 0.0005 to 0.0050%, N: 0.001 to 0.02%, Ca: 0.0015% or less, and Mg: 0.0003% to 0.0030% and having a balance of Fe and impurities, in which steel, when defining complex inclusions including oxides and having a long axis of 1 &#x3bc;m or more as complex inclusions (A) and

Ferritic stainless steel with excellent ridging resistance

An environmentally friendly flux for molten steel desulfurization includes CaO and AlOso that [CaO]/[AlO] is within a range of 1.6 to 3.0, and includes one or more alkali metal oxides of NaO, KO, and LiO, and SiOso that [SiO]/[RO] is within a range of 0.1 to 3, [RO] is within a range of 0.5 mass % to 5 mass %, and [SiO] is within a range of 0.05 mass % to 15 mass % in a case in which the [CaO], the [AlO], the [SiO], and the [RO] represent the mass % of CaO, the mass % of AlO, the mass % of SiO, and the total amount of the mass % of NaO, the mass % of KO, and the mass % of LiO respectively.

Environmentally friendly flux for molten steel desulfurization

In order to quickly and economically evaluate cleanliness of a metal with high representativity when quantities, compositions, etc., of non-metallic inclusion particles existing in a metal and resulting in product defects are evaluated by a sample collected during the production process of the metal, the present invention provides an evaluation method involving the steps of levitation-melting a metal piece for a predetermined time by cold crucible levitation-melting means, discharging non-metallic inclusion particles contained in the metal piece to the surface of a molten metal, and directly analyzing a curved and non-smooth sample surface after solidification by a fluorescent X-ray analysis method using an energy dispersion type spectroscope, or by other chemical or physical measurements, to measure or analyze the quantities of elements constituting the non-metallic inclusion particles and to determine quantity of the non-metallic inclusions.

Evaluation apparatus for cleanliness of metal and method thereof

In order to quickly and economically evaluate cleanliness of a metal with high representativity when quantities, compositions, etc., of non-metallic inclusion particles existing in a metal and resulting in product defects are evaluated by a sample collected during the production process of the metal, the present invention provides an evaluation method involving the steps of levitation-melting a metal piece for a predetermined time by cold crucible levitation-melting means, discharging non-metallic inclusion particles contained in the metal piece to the surface of a molten metal, and directly analyzing a curved and non-smooth sample surface after solidification by dissolving the surface and extracting and filtering the inclusions to measure or analyze the quantities of elements constituting the non-metallic inclusion particles and to determine quantity of the non-metallic inclusions.

Evaluation method for cleanliness of metal

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Tokyo, Japan

Katsuhiro Fuchigami