Honda Giken Kogyo Kabushiki Kaisha

Other

Nippon Steel Corporation

Sumitomo Metals, Ltd.

Seiichi Koike

Mitsuo Takashima

Hiroyuki Horimura

Masao Ichikawa

Noriaki Matsumoto

Hitoshi Matsumoto

Masakazu Sato

Hiroshi Hagiwara

Masayuki Hashimura

Keisuke Ban

Noriyuki Yamada

Toshihiro Oikawa

Nobuhiko Ibaraki

Kazuo Kikawa

Masahiko Nakagawa

Kohei Kubota

Tohru Ohta

Hiroaki Hayashi

Eitarou Koya

Kazunori Fukizawa

Toshinobu Hata

Takanari Miyaki

Katsuaki Shiiki

Zenji Iida

Yoichi Nosaka

Shigeki Muroga

Yoshihiko Kamada

Masato Kurita

Mitsuo Uno

Tomoyoshi Matsuno

Kazuhiro Washizu

Sadafumi Yoshino

Shouich Suzuki

Katsuhiro Tsukiyama

Yuichi Namimura

The present invention provides a steel wire, for springs excellent in coiling property while having a high strength, as a heat treated steel wire for high strength springs, characterized by: comprising, in mass, C: 0.75 to 0.85%, Si: 1.5 to 2.5%, Mn: 0.5 to 1.0%, Cr: 0.3 to 1.0%, P: not more than 0.015%, S: not more than 0.015%, N: 0.001 to 0.007%, W: 0.05 to 0.3%, and the balance consisting of Fe and unavoidable impurities; having a tensile strength of not less than 2,000 MPa; spheroidal carbides, composed of mainly cementite, observed in a microscopic visual field satisfying the area percentage of the spheroidal carbides not less than 0.2 &#x3bc;m in circle equivalent diameter being not more than 7%, the density of the spheroidal carbides 0.2 to 3 &#x3bc;m in circle equivalent diameter being not more than 1 piece/&#x3bc;m, and the density of the spheroidal carbides over 3 &#x3bc;m in circle equivalent diameter being not more than 0.001 piece/&#x3bc;m; the prior austenite grain size number being #10 or larger; the content of the retained austenite being not more than 12 mass %; the maximum diameter of carbides being not more than 15 &#x3bc;m; and the maximum diameter of oxides being not more than 15 &#x3bc;m.

Heat-treated steel wire for high strength spring

Material for a connecting rod for an internal combustion engine is carburized and quenched, a carburized layer formed on the bearing portion is ground until the portion which exhibits the maximum compressive residual stress, and a shot-peening processing is performed on the ground surface. The invention produces a bearing portion having surface characteristics in which maximum compressive residual stress is imparted, and therefore, remarkable improvement in the fatigue strength in the bearing portion can be obtained. Furthermore, a large number of concavities formed by the shot-peening processing can be efficiently employed as an oil reservoir, so that sliding properties and lubrication can be improved, and the occurrence of problems such as fretting corrosion, galling, and seize can also be solved, and the galling and problems of the seize can be prevented.

Production process for connecting rod for internal combustion engine

A high-strength bolt having excellent delayed fracture resistance and stress relaxation resistance in addition to a tensile strength of 1200 N/mm or higher is disclosed. A steel material for the high-strength bolt includes C: 0.50 to 1.0% by mass (hereinafter, referred to simply as &ldquo;%&rdquo;), Si: 0.5% or less (not including 0%), Mn: 0.2 to 1%, P: 0.03% or less (including 0%) and S: 0.03% or less (including 0%). The steel material has pro-eutectoid ferrite, pro-eutectoid cementite, bainite and martensite structures at less than 20% in total and a pearlite structure as the remainder. The high-strength bolt is produced by drawing the steel material severely to obtain a steel wire, forming the steel wire into a bolt shape through a cold heading, and subjecting the shaped steel wire to a blueing treatment at a temperature within a range of 100 to 400&deg; C.

Method for manufacturing high strength bolt excellent in resistance to delayed fracture and to relaxation

A metallic mold-casting method excellent in the resistance to penetration is herein disclosed and the method comprises the steps of forming a coating layer by applying a mixture comprising at least one member selected from the group consisting of high melting metals, ceramic materials and graphite, and an aqueous surfactant solution or low boiling liquid oils and fats to at least part of the surface of a metallic mold on its cavity side, then applying heat to the coated portion to thus adhere the mixture to the inner surface of the mold, and thereafter repeatedly casting a magnesium alloy in the metallic mold provided with the coating layer. The metallic mold-casting method permits the metallic mold casting of magnesium alloys with good resistance to penetration and this accordingly leads to the production of a cheap and high quality cast magnesium alloy product.

Method for metallic mold-casting of magnesium alloys

Non-heat treated, soft-nitrided steel parts

An aluminum alloy comprises magnesium in a range of 3.0% by weight&lE;Mg&lE;5.5% by weight, manganese in a range of 1.5% by weight&lE;Mn&lE;2.0% by weight, nickel in a range of 0.5% by weight&lE;Ni&lE;0.9% by weight, and the balance of aluminum including inevitable impurities. Particularly, the Ni content is set in the above range in order to achieve an increase in toughness of a die-cast product. Thus, it is possible to suppress the amount of an intermetallic compound AlMnNi produced and to finely divide the intermetallic compound AlMnNi.

Aluminum alloy for die-cast product having a high-toughness

A heat resistant slide member for an internal combustion engine is a plastically worked member formed from a quenched and solidified aluminum alloy, with a metal flow line in a sliding portion thereof set in a sliding direction. The aluminum alloy contains at least one selected from the group consisting of Cr, Fe, Zr and Ti in an amount of 5% or more and 30% by weight or less and has an average diameter of precipitates and crystallizates therein of 50 .mu.m or less and a tensile strength at 300.degree. C. of 18 kg/mm.sup.2 or more.

Heat resistant slide member for internal combustion engine

A heat-resistant aluminum alloy sinter comprises 5 to 12% by weight of Cr, less than 10% by weight of at least one selected from the group consisting of Co, Ni, Mn, Zr, V, Ce, Fe, Ti, Mo, La, Nb, Y and Hf, and the balance of Al containing unavoidable impurities. A silicon carbide fiber is included for reinforcing the sinter in a fiber volume fraction range of 2 to 30%.

Heat-resistant aluminum alloy sinter and process for production of the

A method for casting a rocker arm made of light alloy for use in an overhead cam shaft type valve operating mechanism of an internal combustion engine, which rocker arm includes a thick-walled bearing section to be fitted on a rocker arm shaft and is integrally provided with a wear-resistive piece having a protrusion on its rear surface and adapted to abut a cam. After molten metal has been injected under pressure into a metallic mold for the rocker arm, a secondary pressurizing force directed in the direction of an imaginary center axis of a rocker arm shaft is exerted by means of a pressurizing rod. In the metallic mold for the rocker arm, a sprue is provided close to the position where the wear-resistive piece is disposed with respect to the position where the bearing section is formed, and the direction of the sprue is directed towards the position where the wear-resistive place is disposed.

Method for producing a rocker arm for use in an internal combustion

This invention relates to a fiber-reinforced metallic member in which an essential part is reinforced by inorganic fibers. The fiber-reinforced metallic member is reinforced by means of a fiber shaped body having a low fiber volume proportion which is formed by mixing powder having the same composition as the metal forming a non-reinforced layer thereof or powder consisting of principal components of the metal with inorganic fibers, the particle diameter of the powder being 1 to 20 times as large as a diameter of the inorganic fibers, and compressing and shaping the mixture. It is also possible to place the layer which is reinforced by the fiber shaped body having a low fiber volume proportion, adjacent to the non-reinforced layer, and to increase a fiber volume proportion in the reinforced layer in the direction of separating from the adjacent reinforced layer. By employing such structure, it is possible to eliminate abrupt change of the characteristics of the materials at the boundary portion between the complex reinforced layer and the non-reinforced layer and to provide a structural member having a good durability.

Fiber-reinforced metallic member

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Wako, Japan

Seiichi Koike