Abstract: A coupling device for equipment implements is described, which coupling device does not impair the lubricity of bearing sections when the equipment is in service, does not cause seizure during rotation of bearings, does not need frequent feeding of grease to the bearing sections from outside, and provides good noise absorbability. The coupling device has such a structure that a metal based contact material 7 capable of storing a lubricating oil and/or lubricant is interposed between an implement bushing 1 made from steel and implement pin 4 of an implement for construction equipment.

Abstract: A crawler having a crawler pin and a crawler bush having lubrication between the crawler pin and the crawler bush without lowering the strength of the crawler at the running time, thereby to prevent the creak or seizure, as might otherwise be caused at the running time. A metallic sliding member having an excellent wear resistance can be arranged in the clearance between the crawler bush and the crawler pin. The metallic sliding member can be capable of holding lubricating oil and/or a lubricant. In addition, the clearance between the core bush and the crawler pin can be narrowed, so that the resulting structure retains the imbalance load on both the crawler bush and the crawler pin.

Abstract: With the objectives of alleviating the property of attacking on the mating member by scratching-off of local agglutinates on the sliding contact surface, achieving improved wear resistance, and achieving improved seizure resistance through restraint of frictional heat generation by a hard phase, a copper based sintered contact material contains shock-resistant ceramics in an amount of 0.05 to less than 0.5 wt % as non-metallic particles composed of one or more substances selected from pulverized oxides, carbides and nitrides. The shock-resistant ceramics are comprised of SiO2 and/or two or more substances selected from SiO2, Al2O3, LiO2, TiO2 and MgO.

Abstract: There is provided a sintered material of which dimensional accuracy has been increased by improving the sinterability of Cu—Al based sintered material. More specifically, there are provided a sintered material and a composite sintered contact component, which are excellent in strength, wear resistance, seizure resistance and corrosion resistance. The sintered material is a Cu—Al based sintered material containing at least 1 to 12 wt % Sn and 2 to 14 wt % Al, and the composite sintered contact component is formed by sinter-bonding this sintered material to a metal baking.

Abstract: A primary purpose is to provide an inexpensive high-toughness wear-resistant steel having satisfactory toughness where its hardness is HRC 55 or more. This steel contains at least 0.21 to 0.80 wt % C; 0.3 to 2.0 wt % Al; and 0.5 to 4.0 wt % Ni as essential components and further contains alloy elements such as Si, Mn, Cr, Mo, W, V, Ti, Cu and B; unavoidable impurities such as P, S, N and O; and the remainder which substantially consists of a tempered martensitic steel of Fe.

Abstract: A contact material which provides improved wear resistance as well as reduced adhesion utilizing the features of an intermetallic compound having an ordered phase, with the intention of (i) improving the seizure resistance and/or wear resistance of an implement bearing which slides under low-speed, high-surface-pressure conditions and is susceptible to lubricant starvation; (ii) preventing abnormal noises; and (iii) achieving prolonged greasing intervals. The contact material contains 10% by volume or more a metallic alloy phase having such a composition range that causes an order-disorder transition. The metallic alloy phase is a Fe base alloy phase containing one or more elements selected from the group consisting of Al, Si, Co and Ni.

Abstract: High surface pressure resistant steel parts and their producing methods are disclosed. These steel parts are useful as gears, cams, bearings and similar high-strength compact steel articles which are required to have wear resistance and strength to withstand fatigue in rolling or rolling-slipping applications. In a steel part formed according to the invention, a fine nitride and/or carbonitride having at least an average grain size of 0.3 &mgr;m or less is dispersed in the contact surface structure; a multi phase structure composed of martensite, which is divided into extremely fine pieces, forming a disordered shape, by the nitride and/or carbonitride, is formed; and a carbide having a grain size of 3 &mgr;m or less is dispersed to increase the hardness of the surface.

Abstract: There are disclosed copper-base and/or iron-base contact materials which contain a Pb intermetallic compound dispersedly precipitated therein and which have highly improved sliding properties. Double layered contact elements improved in oil impregnation and lubricity are formed by sinter bonding the above contact materials to an iron-base metal backing, respectively. Economical producing methods for such double layered contact materials are also disclosed. In the copper-base and/or iron-base contact materials, one or more kinds of Pb intermetallic compounds are dispersedly precipitated.

Abstract: High surface pressure resistant steel parts and their producing methods are disclosed. These steel parts are useful as gears, cams, bearings and similar high-strength compact steel articles which are required to have wear resistance and strength to withstand fatigue in rolling or rolling-slipping applications. In a steel part formed according to the invention, a fine nitride and/or carbonitride having at least an average grain size of 0.3 &mgr;m or less is dispersed in the contact surface structure; a multi phase structure composed of martensite, which is divided into extremely fine pieces, forming a disordered shape, by the nitride and/or carbonitride, is formed; and a carbide having a grain size of 3 &mgr;m or less is dispersed to increase the hardness of the surface.

Abstract: Crawler belt bushings and their producing methods, with which productivity and cost performance can be improved over the carburization treatment and the induction hardening treatment. After a workpiece made from steel is heated from its outer circumferential surface such that at least the surface temperature of the inner circumferential surface of the workpiece is raised to a quenching temperature, a series of quenching operation is performed to form quench hardened layers which extend toward the core from the inner and outer circumferential surfaces respectively and a soft, imperfectly hardened layer between these quench hardened layers. The quenching operation comprises: cooling the workpiece from the inner circumferential surface; cooling the workpiece from the inner circumferential surface while heating from the outer circumferential surface; and cooling the workpiece from the outer circumferential surface.

Abstract: There are disclosed copper-base and/or iron-base contact materials which contain a Pb intermetallic compound dispersedly precipitated therein and which have highly improved sliding properties. Double layered contact elements improved in oil impregnation and lubricity are formed by sinter bonding the above contact materials to an iron-base metal backing, respectively. Economical producing methods for such double layered contact materials are also disclosed. In the copper-base and/or iron-base contact materials, one or more kinds of Pb intermetallic compounds are dispersedly precipitated.

Abstract: For easily producing a toothed material for high-strength gears etc. with a plastic working technique, deformation resistance occurring in plastic working is reduced and stable high precision plastic working is enabled at lower temperatures. One or more types of heat treatment selected from carburization, carbonitriding and nitriding and a hardening process are applied to an alloy steel material containing: iron as a main component; at least 1.0 to 4.5 wt % Si; 0.35 wt % or less C; and balance Fe and unavoidable impurities, whereby a rolling element is obtained which has a surface layer mainly composed of martensite containing no &agr;-Fe phase and of residual austenite and an inner structure cooled from an (&agr;+&ggr;)-Fe two phase region.

Abstract: Crawler belt bushings and heir producing methods, with which productivity and cost performance can be improved over the carburization treatment and the induction hardening treatment. After a workpiece made from steel is heated from its outer circumferential surface such that at least the surface temperature of the inner circumferential surface of the workpiece is raised to a quenching temperature, a series of quenching operation is performed to form quench hardened layers which extend toward the core from the inner and outer circumferential surfaces respectively and a soft, imperfectly hardened layer between these quench hardened layers. The quenching operation comprises: cooling the workpiece from the inner circumferential surface; cooling the workpiece from the inner circumferential surface while heating from the outer circumferential surface; and cooling the workpiece from the outer circumferential surface.

Abstract: A carburizing method is described which is capable of dispersing cementite grains in the surface of steel uniformly and finely as not to affect fatigue strength and capable of fining the crystal grains of austenite. To prevent cementite precipitation during high temperature carburization at 980° C. or more, steel contains Al in an amount in the range of 0.05≦[Al wt %]≦2.0 and Cr in an amount in the range of 0.3≦[Cr wt %]≦4.0, and the composition of the steel satisfies the requirement represented by 1.9≧−5.6[Si wt %]−7.2[Al wt %]+1.1[Mn wt %]+2.1[Cr wt %]−0.9[Ni wt %]+1.1[Mo wt %]+0.6[W wt %]+4.3[V wt %].

Abstract: High surface pressure resistant steel parts and their producing methods are disclosed. These steel parts are useful as gears, cams, bearings and similar high-strength compact steel articles which are required to have wear resistance and strength to withstand fatigue in rolling or rolling-slipping applications. In a steel part formed according to the invention, a fine nitride and/or carbonitride having at least an average grain size of 0.3 &mgr;m or less is dispersed in the contact surface structure; a multi phase structure composed of martensite, which is divided into extremely fine pieces, forming a disordered shape, by the nitride and/or carbonitride, is formed; and a carbide having a grain size of 3 &mgr;m or less is dispersed to increase the hardness of the surface.

Abstract: A self-lubricating sintered sliding member and its producing method, the member having excellent seizing resistance and wear resistance even in offset load and high load applications.The self-lubricating sintered sliding member is composed of an iron-family metal substrate and a sintered contact layer that is formed on a sliding side of the iron-family metal substrate and made from a sintered contact material containing an iron-family material. The sintered contact layer has, on a surface thereof, protrusions formed from solid lubricant particles including graphite. A solid lubricant layer is laid over the surface of the sintered contact layer where the protrusions are formed.

Abstract: A sinter-joining method for forming a sinter of high quality at low cost and a sintered composite member produced by the sinter-joining method.A tubular copper-base material is forced into a tubular iron-base material and these materials are sintered at temperatures equal to and higher than 600.degree. C. so that the copper-base material expands and pressure-joins to the iron-base material. Then, the materials are sintered at temperatures equal to and higher than 850.degree. C. so that the compactness of the copper-base material is increased. Through these steps, the sintered composite member containing the copper-base material joined to the inside of the iron-base material is obtained.

Abstract: A water solvent extraction degreasing method capable of reducing degreasing time without consideration of abrupt decomposition/vaporization and swelling caused by heat. An organic binder is removed from a molded product that is produced by a powder material mixed with the organic binder and this organic binder contains at least one water-soluble organic compound and at least one water-insoluble thermoplastic resin. The degreasing step of this method includes a water solvent extraction step for extracting the water-soluble organic compound from the organic binder contained in the molded product, using water as a solvent.

Abstract: A low-cost thermal decomposition degreasing method capable of drastically reducing the time required for a degreasing process which involves heating, vaporization and thermal decomposition, while assuring the shape retention property of an injection molded product during degreasing. The degreasing process comprises: (i) a first step wherein a molded product placed under a reduced pressure less than or equal to atmospheric pressure is heated at a temperature lower than the melting point of a thermoplastic binder so that the thermoplastic binder partially evaporates by 5 wt % or more, and then the molded product is further heated at a temperature lower than higher one of the melting points of a more volatile organic compound and a thermoplastic resin whereby the thermoplastic binder further evaporates by 10 wt % or more, and wherein the final temperature is set to 200.degree. C.

Abstract: By the use of a binder comprising (a) 40 to 70 wt % of a water-soluble amide material and/or water-soluble amine material and (b) 25 to 60 wt % of a polyamide resin component substantially composed of a polyamide resin material having 10 carbon atoms or more on average between amido groups, a molded article is produced by metal powder injection molding.From such a molded article, the water-soluble amide material and/or water-soluble amine material is eluted by a water-based solvent and then, the polyamide resin component is removed by heating.