Abstract: Gas shielded arc welding is performed using gas nozzle 10 which comprises a straight portion 14 that permits the shielding gas flows from orifices 18 to flow parallel to the axial direction and a constricted portion 20 continuous from the straight portion 14 that constricts the gas flows from the straight portion 14 as they travel toward the distal end and the nozzle 10 satisfies the following relations (1) and (2):

Abstract: A bearing mechanism eliminates the need for lubricating oil, is capable of generating enough radial dynamic pressure even in lower-speed regions, and yet can be easily surface-machined for the generation of radial dynamic pressure and manufactured with low cost. In at least either one of an outer circumferential surface 2a of a first member 2 or an inner circumferential surface 3a of a second member 3 (hereinafter, referred to as roughened surface), the two circumferential surfaces being opposed to each other with a bearing gap G therebetween, dot-like minute dips and bumps are formed dispersedly, by which the surface is roughened so that its center-line mean roughness is controlled within a range of 0.1 &mgr;m-1.0 &mgr;m.

Abstract: A multi-layered heat resistant metal tube is disclosed. This tube has excellent anti-coking characteristics and is suitable for use under the conditions where carbon tends to deposit and accumulate thereon due to contacting with hydrocarbons at a high temperature. The tube is made by forming weld-mounted overlaid layer of a Cr—Ni—Mo alloy by building-up welding over the inner surface and/or the outer surface of a substrate tube made of a heat resistant metal. The Cr—Ni—Mo alloy consists essentially of, by weight %, Cr: 36-49 wt %, Ni: 35-63 wt % and Mo: 0.5-5 wt %. Building-up welding is preferably carried out by PPW (Plasma Powder Welding) in which the filler metal is supplied in the form of powder.

Abstract: A metal pipe expander which is inserted into a metal pipe and driven to move in the axial direction of the metal pipe by a liquid pressure has an expanding section and a pressure receiving section. The expanding section has a conical portion of which a small diameter portion is directed to a front side. The pressure receiving section has a cup shaped portion opened to the rear side, the outer surface of which is in slide contact with an inner surface of the metal pipe after it is expanded in diameter. The pressure receiving section is provided at a rear end of an expanding section.

Abstract: A method for evaluating bonding properties of a metallic pipe, the method comprises steps of measuring, in advance of a pipe expansion operation, at least one selected from a degree of shape discontinuity, a degree of defect at a bonding portion, and a degree of change in crystal structure, and comparing a measurement value with a predetermined threshold value to evaluate suitability of the bonding properties for applying pipe expansion.

Abstract: A method for examining bonded-metal by ultrasonic examination, the method comprising a step of measuring an attenuation amount of an ultrasonic wave, the ultrasonic wave being generated by a sending probe and received by a receiving probe through a bonding interface, the sending probe and the receiving probe being disposed on the bonded-metal with putting the bonding interface therebetween, the bonded-metal being bonded under unknown condition, and a step of examining a bonding property of the bonded-metal based on the attenuation amount, with utilizing a relationship between a bonding property and an attenuation amount for standard metal bonded under known condition measured preliminarily.

Abstract: A diffusion bonding method having a step of adjusting ends of material to be bonded before bonding the material after setting the materials in the diffusion bonding apparatus, whereas a diffusion bonding apparatus having a means of finishing ends of materials to be bonded so that both ends face parallel to each other.

Abstract: A motor component covered with a novel electrocoating that fails to detrimentally affects magnetic memory medium provided in a hard disc or other is provided. With enhanced edge covering ratio, an improved insulation coating is easily formed on the motor component. An insulation coating is electrodeposited on an Nd—Fe—B system plastic magnet, a stacked core of silicon steel, a die-cast motor base of aluminum or other motor component through cationic electrodeposition. The electrodeposition paint for use includes 12 ppm or less of tin content in the aqueous solution, 0.5% or less by weight of carbon black content in the aqueous solution, and, instead, has titanium dioxide and/or silicon dioxide added to pigment. The electrodeposited insulation coating, which has a specified thickness, is heated to temperatures ranging between 40° C. and 90° C. After such preliminary curing, temperatures are again heated to between 150° C. and 190° C.

Abstract: A steel product contains, by mass %, C: 0.45 to 0.60%, Si: 0.01 to 0.15%, Mn: 0.20 to 0.60%, S: 0.012% or lower, Al: 0.015 to 0.040%, Ti: 0.005 to 0.050%, B: 0.0005 to 0.0050%, N: 0.010% or lower, O: 0.0010% or lower, and balance being Fe and unavoidable impurities. Limitations are provided to allowable maximum sizes per each sort of contained non-metallic inclusions and the number per unit area thereof. This steel may contains one kind or two kinds or more of Cr: 1.00% or lower, Mo: 0.50% or lower and Ni: 1.50 or lower.

Abstract: In a core material for the noise filter, powders of a flat and soft magnetic material is dispersed and buried into an insulating material such as rubber or plastic.

Abstract: A vertical diffusion bonding apparatus is provided with a lower block, a pressurizing jig which is fitted to a metal pipe supplied from an upper position, and a pressurizing mechanisms stood erect on the lower block. The lower metal pipe is held by the lower block and the pressurizing jig bonded to the metal pipe is attracted toward the lower block by using the pressurizing mechanisms. Thus, the metal pipe which is supplied from an upper position is pressed against the lower metal pipe.

Abstract: A joining alloy of the invention is based on Co, Ni, or their alloy, and contains 1.0 to 2.3% by mass of C and 15.5 to 34.7% by mass of W. Using HIP, the joining alloy in the form of a casting or powders is integrated with a WC--Co or WC--Ni type cemented carbide via diffusion joining. Using HIP, it is also possible to obtain a composite material having an integral structure in which a cemented carbide and the joining alloy, and the joining alloy and steel are joined together via diffusion joining. The joining alloy may additionally contain up to 30% by mass of Fe, up to 3% by mass of Si and up to 3% by mass of Mn as well as up to 10% by mass of at least one selected from Cr, Mo, V, Nb, Ti, Zr, and Ta. It is thus possible to obtain a joining alloy having an improved joining strength without producing a brittle phase therein even upon joined to the WC--Co or WC--Ni type cemented carbide, and its composite material.

Abstract: In a method of bonding ferric and austenitic dual stainless steels, an insert material made of a Ni base alloy having a melting point below 1290.degree. C. is put between the bonding cross section faces of mother material steels comprising a dual phase stainless steel. A pressure force in the range of 3 MPa to 5 MPa is applied to a bonding area. The bonding area is heated at a temperature in the range of 1290.degree. C. to a melting point of the mother material steel. The temperature is kept for in the range of 30 second to 180 second.

Abstract: A corrosion resistant sintered body having excellent ductility is provided by sintering, at temperatures of not less than 1050 to less than 1300.degree. C., powders which are composed by adding metal compound of B to and mixing with powders of ferrite stainless steel containing C.ltoreq.0.1 wt %, Si.ltoreq.3.0 wt %, Mn.ltoreq.0.30 wt %, Ni.ltoreq.2.0%, 11 wt %.ltoreq.Cr.ltoreq.22 wt %, Mo.ltoreq.3.0%, and the rest being substantially Fe, at an amount of B in the mixed powders being between more than 0.03 wt % and less than 0.2 wt % based on the weight of the powder.

Abstract: A high corrosion resisting alloy for use in inlet and exhaust valves of diesel engines which is low in cost and excellent in corrosion resistance and strength, which consists by weight percentage of C.ltoreq.0.1%, Si.ltoreq.1.0%, Mn.ltoreq.1.0%, 25%<Cr.ltoreq.32%, 2.0%<Ti.ltoreq.3.0%, 1.0%.ltoreq.Al.ltoreq.2.0% and the balance being Ni and incidental impurities. The valves for the diesel engines are manufactured through the steps of forging the above-mentioned alloy into near net shapes of the valves, performing aging treatment (after solid solution treatment according to demand), and further enhancing hardness of the valves at their valve faces locally through partial cold forging.

Abstract: In a metal material bonding method, an insertion material, which has a lower melting point than that of metal materials to be bonded, is interposed between bonding end surfaces of the metal materials to be bonded. The metal materials to be bonded is heated and held to a temperature not lower than the melting point of the insertion material and not higher than the melting point of the metal materials to be bonded while applying pressure to bonding surfaces of the metal materials to be bonded. The insertion material is formed to have a size which is smaller than each of the bonding surfaces of the metal materials to be bonded.

Abstract: A water cooled finger for a pre-heater of a furnace top holds metal materials of a required amount in a shaft installed at the furnace top for pre-heating metal materials by introducing exhaust gas at high temperature generated in the furnace into the shaft. The water cooled finger is formed of a pair of side aces, an upper plate and a lower plate. The upper plate is fixed to an upper plate of both of the side face portions. The lower plate is fixed to a lower plate of both of the side face portions. The water cooled finger is formed to be hollow as a whole by the side face, the upper plate and the lower plate. The water cooled finger satisfies at least one of the conditions of (A) a thickness of the upper plate is thicker than that of said lower plate, (B) the lower plate is formed to be R-bending processed portions at both ends thereof, and(C) the lower plate is curved outside.

Abstract: A bonding insert material mounting method includes the following steps. A bonding insert material having projections of a suitable shape formed on an outer periphery thereof at predetermined intervals is held by half-splittable holder into which joining members can be inserted in such a manner that the projections are held by the holder and that the bonding insert material is disposed at that area of the holder into which the joining members P can be inserted. One end of the holder on an end of one of the joining members is fitted so that one side of the bonding insert material is abutted against an end surface of the one joining member. An end of the other joining member is inserted into the other end of the holder, so that the end of the other joining member is abutted against the other side of the bonding insert material with a predetermined pressing force. Then, the holder is divided into two division members, and the holder is removed from the joining members.

Abstract: A non-magnetic stainless steel, which contains stably a large amount of N, is excellent in the corrosion resistance and the strength and possible to obtain sound ingots and products, consists by weight percentage of C.ltoreq.0.08%, Si.ltoreq.0.50%, 13%.ltoreq.Mn.ltoreq.16%, P.ltoreq.0.040%, S.ltoreq.0.030%, 0.35%.ltoreq.Cu.ltoreq.1.00%, 2.50%.ltoreq.Ni.ltoreq.5.50%, 17.0%.ltoreq.Cr.ltoreq.19.0%, 0.5%.ltoreq.Mo+W.ltoreq.1.0%, 0.38%.ltoreq.N.ltoreq.0.60%, 0.ltoreq.0.0100%, sol-Al.ltoreq.0.05% and the balance Fe on condition that86(Ni+Cu).gtoreq.13Cr+19Mo+9W+2Mn.

Abstract: Powder is composed of ferrite stainless steel containing: C: .ltoreq.0.1 wt %, Si: .ltoreq.3.0 wt %, Mn: .ltoreq.0.30 wt %, Ni: .ltoreq.2.0 wt %, Cr: 11 to 22%, Mo: .ltoreq.3.0 wt %, and the rest being substantially Fe. The metal compound of B, preferably CrB, is added to the powder as the amount of B being between more than 0.03 wt % and less than 0.2 wt % based on the amount of the powder.