Kawasaki Steel Corporation

Other

Honda Giken Kogyo Kabushiki Kaisha

Toshiyuki Hoshino

Keniti Amano

Takashi Iwamoto

Kazukuni Hase

Yasuhiro Omori

Akihiro Matsuzaki

Tohru Hayashi

Masahiro Furukawa

Toshio Fujita

Hiroshi Murakami

Kikuo Maeda

Fumimaru Kawabata

Kazuhiko Shiotani

Kimihiro Nishimura

Akio Okayama

Isao Machida

Nobuhisa Tabata

Masayoshi Saga

Takeshi Takagi

Takuya Atsumi

Yasuyashi Yamane

Absorption refrigerator control method

Absorption refrigerator

Provided is a non heat-treated steel that requires no particular controls over cooling rates and no aging treatments after hot working, that can sufficiently increase tensile strength, yield strength and toughness even at lightly deformed parts, and furthermore, that has excellent material anisotropy and machinability as an alloy steel for machine structures. In other words, it is a non heat-treated steel that contains: C: more than 0.05 mass % to less than 0.10 mass %; Si: 1.0 mass % or less; Mn: more than 2.2 mass % to 5.0 mass %; S: less than 0.020 mass %; Cu: more than 1.0 mass % to 3.0 mass %; Ni: 3.0 mass % or less; Cr: 0.01 to 2.0 mass %; Al: 0.1 mass % or less; Ti: 0.01 to 0.10 mass %; B: 0.0003 to 0.03 mass %; N: 0.0010 to 0.0200 mass %; O: 0.0060 mass % or less; and the balance Fe and inevitable impurities, and that the steel structure is bainitic having block structures at 10% or more in area ratios.

Non-refined steel being reduced in anisotropy of material and excellent in strength, toughness and machinability

In a rolling bearing having a rolling bearing ring and a rolling element of at least 20 mm in diameter, at least one of the rolling bearing ring and the rolling element consists of carburized or carbonitrided steel containing at least 0.2 wt % and not more than 0.35 wt % of carbon and at least 2.2 wt % and not more than 3.6 wt % of Ni. Thus obtained is a rolling bearing capable of reducing the material cost and increasing the fatigue life or reducing the carburizing time by ensuring surface hardness and optimizing the case depth.

Rolling bearing

High-strength and high-toughness non heat-treated steel having excellent

The invention provides a steel product having superior weathering which is coated with a rust layer containing 50 or more weight % of non-crystalline rust, a method of producing the steel product, and a method of forming weathering protective rust on a material surface of the steel product. A material of a steel product is placed in an atmosphere in which the dew point is kept constant and the temperature of the steel product material is repeatedly varied between a temperature range of 5.degree. C. or more higher than the dew point and a temperature range of 5.degree. C. or more lower than the dew point. Weathering protective rust is thereby formed on the material surface of the steel product and a steel product having superior weathering is obtained. Preferably, the atmosphere contains 15 to 50 volume % of oxygen gas, and the temperature of the steel product is varied at a rising rate of 0.1 to 2.degree. C./minute and a lowering rate of 0.01 to 2.degree. C./minute. Alternatively, a desired steel product can also be obtained by placing a material of the steel product in an atmosphere containing 15 to 50 volume % of oxygen gas, keeping constant the dew point in the atmosphere, and keeping the temperature of the steel product material in the atmosphere at a certain value in a temperature range between a temperature 5.degree. C. lower than the dew point and a temperature 20.degree. C. lower than the dew point; or by placing a material of the steel product in an atmosphere containing 15 to 50 volume % of oxygen gas, and forming and keeping a water film with a thickness not more than 500 .mu.m but not less than 50 .mu.m on a material surface of the steel product.

Steel products having superior weathering, method of producing the steel

Graphite steel for a machine structural use exhibiting excellent cutting characteristic, cold forging characteristic and fatigue resistance, the graphite steel for a machine structural use containing: C: 0.1 wt % to 1.5 wt %; Si: 0.5 wt % to 2.0 wt %; Mn: 0.1 wt % to 2.0 wt %; B: 0.0003 wt % to 0.0150 wt %; Al: 0.005 wt % to 0.1 wt %; O.ltoreq.0.0030 wt %; P.ltoreq.0.020 wt %; S.ltoreq.0.035 wt %; N: 0.0015 wt % to 0.0150 wt %; and a balance consisting of Fe and unavoidable impurities, wherein substantially overall quantity of C is precipitated as graphite and size of graphite is 20 .mu.m or less.

Graphite steel for machine structural use exhibiting excellent free

Method of manufacturing steel for machine structural use exhibiting

A carbon steel useful for machine structural use having improved cold forgability and induction hardenability comprises particular amounts of C, Si, Mn, Cr, S, P, O, N or further Mo and the balance being substantially Fe.

Carbon steel for machine structural use

Growing community of inventors

Okayama, Japan

Toshiyuki Hoshino