Honda Giken Kogyo Kabushiki Kaisha

Honda Motor Co., Ltd.

Kazuo Ishii

Yoshihiro Odagiri

Hiroshi Hashimoto

Takashi Komatsuda

Shinichi Takahashi

Seiji Kato

Koichi Fujimori

Masaru Enomoto

Yoshinari Okada

Hideo Kaiho

Kazuhiro Furuhashi

Hitoshi Ishii

Tatsumi Yamada

Kouichi Fujimori

Yasunori Konishi

Makoto Nakada

Takeshi Munemura

Tatsumi Tanaka

A method for producing a carburized part by carburizing a steel member under a vacuum in a decompression furnace while feeding carburizing gas comprises a step for forming an oxide film on at least a part of a surface of the steel member, a step for generating carbon by reducing the oxide film with the carburizing gas, and a step for carburizing the surface of the steel member under a vacuum by diffusing the carbon.

Method for producing carburized parts

A steel strip made of martensitic steel contains C+N at not more than 0.12 wt %, Si at not more than 1 wt %, Mn at not more than 7 wt %, Ni at 2 to 24 wt %, Cr at 2 to 16 wt %, Mo at not more than 2.5 wt %, and Ni-Bal value and Ms value defined by the following equations shown by weight percentage of each composition are respectively Ni-Bal&#x2267;1.2, Ms&#x2267;&#x2212;28.Ni-Bal=Ni+0.5Mn+30(C+N)&#x2212;1.1(Cr+1.5Si)+8.2Ms=502&#x2212;810C 1230N&#x2212;13Mn&#x2212;30Ni&#x2212;12Cr&#x2212;54Cu&#x2212;46Mo

Steel hoop made from a martensitic steel strip

In the present invention, after a nitriding process is performed on a steel, a passivating process in which the steel is heated under an atmosphere containing oxygen is performed. The heating condition of the passivating process is within a range surrounded by (100&#xb0; C., 120 min), (100&#xb0; C., 10 min), (125&#xb0; C., 5 min), (190&#xb0; C., 5 min), (200&#xb0; C., 10 min), (200&#xb0; C., 20 min), (190&#xb0; C., 30 min), (190&#xb0; C., 40 min), (180&#xb0; C., 60 min), and (180&#xb0; C., 120 min) on coordinate axes of temperature and time. In the process for production of the nitrided steel, uniform passivated layer can be easily formed, and fatigue strength is improved as pitting corrosion resistance is improved.

Method for producing nitriding steel

A hoop for a CVT belt including foreign matter existing in a nitrided hardened layer and surface of the hoop, the foreign matter comprises at least one of an oxide-type foreign matter, a nitride-type foreign matter, and a carbide-type foreign matter. The oxide-type foreign matter has a particle size of 25 &#x3bc;m or less, the nitride-type foreign matter and/or the carbide-type foreign matter have particle sizes of 17 &#x3bc;m or less.

Hoop for CVT belt and manufacturing method therefor

A fatigue test device for thin plates can reliably perform tests. The fatigue test device has a rod having ends in a longitudinal direction thereof; a vibration source for excitating a longitudinal end of the rod in the longitudinal direction thereof so as to form a standing wave having node portions and antinode portions formed therebetween and a mounting means for mounting a test piece having a longitudinal direction at one of the antinode portions, the test piece being positioned such that the longitudinal direction thereof is perpendicular to the longitudinal direction of the rod.

Fatigue test device and method for testing the thin plate

A method for producing a steel material having a high fatigue strength and given a uniform residual stress by a rapid treatment. A marageing steel is subjected to a cold plastic working to have a predetermined dimension, to a solution treatment for 60 minutes or more at a temperature of 750 to 800&#xb0; C., and to an aging.

Steel material production method

Process for evaluating life of article subjected to thermal cycles based on comparison of strain rates measured under evaluating conditions and actual service conditions

An exhaust manifold M is comprised of a plurality of inner exhaust pipe shells secured to an upper flange, and a plurality of outer exhaust pipe shells secured to the upper flange to individually cover the inner exhaust pipe shells, wherein a downstream end of each of the corresponding inner exhaust pipe shells slidably contacts an annular bead bulging from an outer peripheral surface of the downstream end of the outer exhaust pipe shells. An inner collecting pipe shell communicates with the plurality of inner exhaust pipe shells and is secured at its upstream end to the plurality of outer exhaust pipe shells, and an outer collecting pipe shell which is secured at its upstream end to the plurality of outer exhaust pipe shells covers the inner collecting pipe shell. A downstream end of the inner collecting pipe shell slidably contacts an annular mesh member interposed therebetween. Sliding portions for absorbing a difference in the axial thermal elongation between inner and outer double walls are provided separately at the downstream end of an exhaust single pipe and the downstream end of an exhaust collecting pipe. Thus, the sliding stroke in each of the sliding portions can be set to a small value, and the absorption of the thermal elongation can be carried out smoothly.

Heat-insulation type exhaust manifold

A heat-insulating, light and vibration-proof exhaust manifold for a multi-cylinder internal combustion engine is provided. The exhaust manifold comprises an upper stream flange, a lower stream flange, four manifold pipes at an upper stream, a manifold chamber (gathering section) at a lower stream and a manifold case of a plate metal covering the manifold pipes and the manifold chamber. The manifold pipes have upper stream ends to be connected to exhaust ports of the internal combustion engine through the upper stream flange and lower stream ends gathering in the manifold chamber. Upper stream ends of the manifold pipes and the manifold case are welded to the upper stream flange, and lower stream ends of the manifold chamber and the manifold case are welded to the lower stream flange. The manifold pipe and the manifold chamber can slide relatively at a slide portion which is maintained by pressing the manifold chamber and the manifold case against the manifold pipe.

Growing community of inventors

Wako, Japan

Kazuo Ishii