Abstract: The present invention relates to a cemented carbide and coated cemented carbide which contain free carbons, and provides a cemented carbide which enables to remove or reduce the disadvantages of the free carbons even if the cemented carbide contains the free carbons, specifically to decrease in the strength is reduced by finely dispersing the free carbons even if the cemented carbide contains the free carbons and to obtain a beautiful mirror surface on a mirror-finished surface by finely dispersing free carbons in the cemented carbide. The present invention is a cemented carbide composed of tungsten carbide (WC) and cobalt (Co), which contains carbon in such an amount range that no solid carbon is contained in a liquid phase while the liquid phase is present at a high temperature, characterized in that the maximum diameter of the pores resulting from the free carbons is 20 ?m or smaller.

Abstract: An oil pump for an internal combustion engine is provided with an intake port and a discharge port, each formed in a pump housing. The oil pump has a power pump serving as a first main pump and an electric pump serving as a second auxiliary pump, both of which may be contained in a same pump housing. The power pump is rotated by a driving force of a crankshaft, and the electric pump is rotated by the driving force of an electric motor. This makes it possible to reduce the maximum capacity of the power pump serving as the main pump. In a vehicle operating range where the oil discharging pressure generated by the power pump becomes insufficient, the electric pump serving as the auxiliary pump is operated together with the power pump such that appropriate oil discharging pressure or appropriate oil discharging quantity can be achieved. The electric pump may also be allowed to operate for a period of time after shutting off of the engine.

Abstract: In a package of a semiconductor device mounted a semiconductor element and micro balls as electric contact points, the micro balls are composed of composite micro balls each of which has a core ball and an electrically conductive film around the core ball. The core balls have a sufficient rolling property with the diameter ranged from 30 to 100 &mgr;m. The diameter accuracy thereof is excellent. The electrically conductive film is formed by a solder plated layer which has a thickness of at least 10 &mgr;m uniformly formed on the outer surfaces. The composite micro balls are mounted onto a substrate. The dimensional accuracy of the Z axis of the package can be precisely controlled. Accordingly, the composite micro balls with the solder plated film has a thickness of at least 20 &mgr;m on the outer circumference of each core ball. The production method thereof, and the semiconductor package mounted a semiconductor element using the composite micro balls can be provided.

Abstract: An oil pump for an internal combustion engine is provided with an intake port and a discharge port, each formed in a pump housing. The oil pump has a power pump serving as a first main pump and an electric pump serving as a second auxiliary pump, both of which may be contained in a same pump housing. The power pump is rotated by a driving force of a crankshaft, and the electric pump is rotated by the driving force of an electric motor. This makes it possible to reduce the maximum capacity of the power pump serving as the main pump. In a vehicle operating range where the oil discharging pressure generated by the power pump becomes insufficient, the electric pump serving as the auxiliary pump is operated together with the power pump such that appropriate oil discharging pressure or appropriate oil discharging quantity can be achieved. The electric pump may also be allowed to operate for a period of time after shutting off of the engine.

Abstract: In order to provide cemented carbide, provision is made about tungsten carbide powder which has a grain size not smaller than 1 .mu.m and which is mixed with carbon powder and chromium powder to form raw powder. The tungsten carbide powder is formed by fine primary crystal particles of tungsten carbide and satisfies an inequality given by:Y>0.61-0.33 log (X),where Y denotes a half-value width of (211) crystal planes in tungsten carbide (JCPDS-card 25-1047, d=0.9020) measured by a X-ray diffraction method and where X denotes a grain size measured by the FSSS method. There is also provided a method of producing the composite carbide powder having tungsten carbide powder as a main element, the method comprising the steps of preparing tungsten powder which has a mean grain size not smaller than 1 .mu.m, mixing the tungsten powder with carbon powder and chromium powder into a mixture, and processing the mixture in a predetermined atmosphere into fine primary crystal particles of tungsten carbide.

Abstract: A ceramic compact having excellent high temperature strength, toughness and reliability, which comprises a matrix preferably composed predominantly of silicon nitride and ceramic fibers uniformly dispersed in the matrix and orientated in a desired direction, said matrix and fibers being closely bonded by sintering. This compact is produced, for example, by preparing a shaped body of silicon, for example, in which ceramic fibers are uniformly dispersed by centrifugal casting and then heating and nitriding the shaped body in a nitrogen atmosphere to form a fiber-reinforced silicon nitride sintered compact. The ceramic fibers may include such fibers as aluminum oxide or silicon carbide fibers. Sintering assistants, such as silicon nitride, may be used to prepare the sintered compact.

Abstract: A ceramic compact having a more excellent high temperature strength, toughness and reliability, which comprises a silicon nitride matrix and ceramic fibers uniformly dispersed in the matrix and orientated in a desired direction, said matrix and fibers being closely bonded by sintering, is provided. This compact is produced, for example, by preparing a shaped body of silicon in which ceramic fibers are uniformly dispersed and then bearing and nitriding the shaped body in a nitrogen atmosphere to form a fiber-reinforced silicon nitride sintered compact.

Abstract: A manufacturing method of super-heat-resisting alloy material characterized in comprising the steps of: (1) filling and sealing the powder of Ni-based super-heat-resisting alloy in a rubber mold; (2) subjecting the powder in the rubber mold to cold isostatic pressing; (3) sintering the compact in vacuum or in gas atmosphere at a temperature of 1000.degree. C. or more so that the sintered density increases to 95% or more than the theoretical density; and (4) next, subjecting the sintered compact to hot isostatic pressing.

Abstract: A method of producing rocket combustors wherein in forming an outer cylin by a powder metallurgical method on the outer side of a cylinder provided on its outer periphery with a cooling wall of channel construction having a plurality of grooves, a low-melting alloy is used as a filler to be filled into the grooves. It is also possible to form the outer cylinder after forming a Cu plating shell on the periphery of the inner cylinder filled with the low-melting alloy.

Abstract: A method of producing rocket combustors wherein in forming an outer cylin by a powder metallurgical method on the outer side of a cylinder provided on its outer periphery with a cooling wall of channel construction having a plurality of grooves (14), an Ni electroforming layer is formed on the outer side of the outer cylinder, and also a method of producing rocket combustors wherein an outer cylinder is of multilayer construction having two or more layers.

Abstract: The present invention relates to a process of physical vapor deposition which homogeneously and tightly coats hard compounds on the surface of cutting tools, parts requiring wear resistance or ornaments such as a watch case and the like in order to improve wear resistance, heat resistance, corrosion resistance, appearance and the like of said tools, parts or ornaments.

Abstract: The invention relates to semiconductor chip mounting substrate for use in semiconductor apparatus, wherein metal material or multi-laminated metal material is coated on its surface and/or lateral faces with thin film of insulated inorganic matter in order to obtain an insulated substrate not only capable of efficiently radiating the heat developed in the semiconductor chip but also having thermal expansion coefficient approximate to that of the semiconductor chip, or further coated with film of Cu or Al so that the substrate is provided with high thermal conductivity and required thermal expansion characteristics thereby enabling to produce semiconductor apparatus highly effective for the acceleration of increase of density, reduction of size and improvement of radiation of IC.

Abstract: This invention relates to a highly hard material coated article which comprises a substrate of tool or part consisting of cermets, cemented carbides, tool steels or stainless steels and at least one highly hard material coated on the surface thereof, selected from the group consisting of carbides, nitrides and carbonitrides of at least one of titanium, zirconium and hafnium and those in which oxygen is dissolved, the coating being formed by an ion plating method wherein the accelerating voltage is high in a short time at the initial stage only, the crystals of the coated film being strongly orientated in the direction of <220> for the surface of the tool or part so that the diffraction intensity ratio of the peak from the {220} plane and the secondly strong diffraction peak in the X-ray diffraction using Cu-K.alpha.

Abstract: The present invention relates to a sintering furnace for powder metallurgy of cemented carbides, cermets and ceramics, which comprises a main furnace body, a heating chamber provided in the main body, a table having a moving means for carrying a workpiece in or out of the heating chamber and a means for cooling the interior of the furnace with a heat exchanger fitted to the exterior of the main furnace body, and a method for the sintering and heat treatment of cemented carbides in the sintering furnace as claimed in claim 1, which comprises sintering cemented carbides and cooling rapidly at a cooling rate of at least 30.degree. C./min from the sintering temperature being at least a temperature at which a liquid phase appears to at most 1000.degree. C. by the use of an inert gas as a coolant.

Abstract: This invention relates to a highly hard material coated article which comprises a substrate of tool or part consisting of cermets, cemented carbides, tool steels or stainless steels and at least one highly hard material coated on the surface thereof, selected from the group consisting of carbides, nitrides and carbonitrides of at least one of titanium, zirconium and hafnium and those in which oxygen is dissolved, the coating being formed by an ion plating method wherein the accelerating voltage is high in a short time at the initial stage only, the crystals of the coated film being strongly orientated in the direction of <220> for the surface of the tool or part so that the diffraction intensity ratio of the peak from the {220} plane and the secondly strong diffraction peak in the X-ray diffraction using Cu-K.alpha.

Abstract: A ceramic sintered body with a high density and high surface smoothness is obtained by sintering a ceramic composition comprising oxides as a substantial or partial component in an atmosphere of CO gas or in a mixture of CO gas and an inert gas.

Abstract: There is provided a coated tool steel having a tool steel substrate and at least one layer of a hard film overcoated on the substrate. The film consists of a B-1 type solid solution selected from carbides, nitrides and carbonitrides of at least one of titanium, zirconium or hafnium, and the breadth of the peak, at half maximum intensity, of Cu-K.alpha. diffraction from the (200) plane of the film, being not less than 0.4 degree on a 2 .theta. scale. The invention further provides a machine tool having at least one cutting part thereof formed from the coated tool steel described above. The coated steel provided herein has excellent wear resistance.

Abstract: A super hard metal roll assembly and a process for producing it are disclosed. Initially, a powdered mix of super hard metal materials is moulded into a hollow cylindrical moulding. The moulding is then fitted about a super hard metal cylindrical element such as roll, cylinder, pillar or shaft, and sintered to contract to a bushing tightly engaging the outer periphery of the cylindrical element to produce a super hard metal roll assembly. The roll assembly may be further treated in a high temperature and high pressure inert gas in order to eliminate voids at the interface between the bushing and the cylindrical element.