Nippon Steel Corporation

Kokusai Electric Co., Ltd.

Heraeus Electronite Japan, Ltd.

Kokoshi Electric Co.

Akihiro Ono

Koichi Chiba

Hiroyuki Kondo

Eiichi Takeuchi

Ryuji Uemori

Takehiko Toh

Kazushige Umezawa

Masamitsu Wakoh

Ryutaro Matsumoto

Tokio Suzuki

Isamu Taguchi

Masaki Okajima

Toshihiro Ogura

Takamasa Ohno

Hiroshi Yamane

Masaki Ina

Hiroaki Kosaka

Minoru Hayata

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

Disclosed herein is a method of sequentially and continuously determining the concentrations of carbon, hydrogen, and nitrogen in molten steel using a single apparatus. Disclosed also herein are a method and an apparatus for determining trace amounts of carbon in molten steel which are the specialized application of the principle used for the above-mentioned method. Said method comprises bubbling through molten steel a carrier gas selected according to any specific element to be determined in molten steel, recovering the carrier gas containing the specific element, circulating or passing the recovered carrier gas through a gas circulating circuit so that the concentration of the specific element in the carrier gas reaches an approximate or complete equilibrium with the concentration of the specific element in molten steel, determining the concentration of the specific element by the means to determine the concentration of one or more specific elements, (and in the case of determination of several elements) discharging the carrier gas from the gas circulating circuit and repeating said steps with a renewed carrier gas to determine the remaining elements to be determined.

Method and apparatus for sequentially and continuously determining

Oxygen or a mixed gas containing oxygen, or a chemical flame produced by a mixture of a combustion gas and a combustion-assisting gas containing oxygen, is blown against the surface of molten iron to cause radiation emission. The radiations are divided into components of different wavelengths, and the resulting emission spectra are measured to determine the composition of the molten iron.

Method of spectroscopically determining the composition of molten iron

In an automatic photometric analyzer, an injector and a coloring source deliver a respective sample solution and a coloring solution to a reactor to form a reactant. The reactant is circulated through an absorbency-measuring photometric device and back to the reactor.

Automatic photometric analyzer

An automatic photometric analyzer is disclosed using an automatic exchanger holding a sample solution. A recorder, a photometer, an injector for the sample solution, and supply systems for pure water and coloring solutions are used. Additionally, valves under control of an automatic controller properly control the flow and the solution to provide a simple and practical apparatus with rapid automatic operation for analysis. The injector delivers reactant solutions to a reactor from which reactant is circulated through the photometric means to measure the absorbency thereof and back to the reactor.

A method for automatically dissolving solid analysis samples in powder form which comprises transferring the sample from an external source into a dissolving tank under reduced pressure, adding a predetermined amount of dissolving solution, and taking out the solution. A condenser is provided at the top of the dissolving tank to effect condensation of vapor rising therefrom and the reduced pressure for transferring the sample is applied by vacuum means through the condenser.

Method and apparatus for automatically dissolving samples for anaylsis

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Kawasaki, Japan

Akihiro Ono