Abstract: According to the present invention, it is possible to obtain a copper alloy laminated and shaped object having a high strength and a high electrical conductivity. This invention provides a copper alloy powder for laminating and shaping, wherein the copper alloy powder contains a chromium element an amount of which is equal to or more than 0.40 wt % and equal to or less than 1.5 wt %, a silver element an amount of which is equal to or more than 0.10 wt % and equal to or less than 1.0 wt %, and a balance of pure copper and unavoidable impurities.

Abstract: This invention provides a copper powder to which tin (Sn) is added such that a high-density laminated and shaped product can be obtained by a laminating and shaping method using a fiber laser as a heat source by appropriately reducing the electrical conductivity of copper, so a laminated and shaped product having a high density and a high electrical conductivity can be obtained. That is, this invention provides a copper powder for lamination shaping in which a tin element is added to pure copper. Desirably, the copper powder contains 0.5 wt % or more of the tin element. More desirably, the copper powder contains 5.0 wt % or more of the tin element. When the product has an electrical conductivity sufficient as a copper product, the copper powder desirably contains 6.0 wt % or less of the tin element. Furthermore, no element other than the tin element is desirably added to the copper powder.

Abstract: In this invention, a copper powder to which phosphorus (P) is added is developed such that a high-density laminated and shaped product can be obtained by a laminating and shaping method using a fiber laser as a heat source by appropriately reducing the electrical conductivity of copper, so a laminated and shaped product having a high density and a high electrical conductivity can be obtained. This invention is a copper powder for lamination shaping in which a phosphorus element is added to pure copper. The copper powder desirably contains 0.01 wt % or more of the phosphorus element. The copper powder more desirably contains 0.04 wt % or more of the phosphorus element. The copper powder desirably contains 0.30 wt % or less of the phosphorus element. The copper powder more desirably contains 0.24 wt % or less of the phosphorus element. No element other than the phosphorus element is desirably added to the copper powder.

Abstract: This invention relates to a method of evaluating a squeegeeing property of powder for lamination shaping by stable criteria. In this method, the squeegeeing property is evaluated using at least a satellite adhesion ratio of the powder and an apparent density of the powder. The satellite adhesion ratio is the ratio of the number of particles on which satellites are adhered to the number of all particles. If the satellite adhesion ratio is equal to or less than 50%, and the apparent density is equal to or more than 3.5 g/cm3, the squeegeeing property is evaluated as that the powder can be spread into a uniform powder layer in the lamination shaping. Furthermore, if the 50% particle size of a powder obtained by a laser diffraction method is 3 to 250 ?m, the squeegeeing property is evaluated as that the powder can be spread into a uniform powder layer in the lamination shaping.

Abstract: This invention relates to a method of evaluating powder for lamination shaping by stable criteria. In this method, it is evaluated whether powder for lamination shaping can be spread into a uniform powder layer in the lamination shaping, wherein the powder is evaluated using, as a flowability of the powder, an adhesive force of the powder calculated from a failure envelope obtained by a shear test. The shear test is conducted by a powder rheometer, and the adhesive force is obtained from the relationship between a normal stress and a shearing stress at the powder rheometer. If the adhesive force is 0.450 kPa or less, the powder is evaluated to be spread into a uniform powder layer in the lamination shaping. Furthermore, if at least one of that the 50% particle size of the powder obtained by a laser diffraction method is 3 to 250 ?m and that the apparent density of the powder is 3.5 g/cm3 or more is satisfied, the powder is evaluated to be spread into a uniform powder layer in the lamination shaping.

Abstract: The present invention provides a laminating and shaping copper powder capable of shaping a laminated and shaped object of copper having a high electrical conductivity of, for example, 80% IACS or more. The present invention is a laminating and shaping copper powder obtained by mixing a nano-oxide of equal to or more than 0.01 wt % and equal to or less than 0.20 wt % and a pure copper powder. There is also provided a laminated and shaped object using the laminating and shaping copper powder of the present invention. There are also provided a manufacturing method of the laminated and shaped object using the laminating and shaping copper powder of the present invention and a laminating and shaping apparatus using the laminating and shaping copper powder.

Abstract: This invention relates to a method of evaluating powder for lamination shaping by stable criteria. In this method, it is evaluated whether powder for lamination shaping can be spread into a uniform powder layer in the lamination shaping, wherein the powder is evaluated using, as a flowability of the powder, an adhesive force of the powder calculated from a failure envelope obtained by a shear test. The shear test is conducted by a powder rheometer, and the adhesive force is obtained from the relationship between a normal stress and a shearing stress at the powder rheometer. If the adhesive force is 0.450 kPa or less, the powder is evaluated to be spread into a uniform powder layer in the lamination shaping. Furthermore, if at least one of that the 50% particle sin of the powder obtained by a laser diffraction method is 3 to 250 ?m and that the apparent density of the powder is 3.5 g/cm3 or more is satisfied, the powder is evaluated to be spread into a uniform powder layer in the lamination shaping.

Abstract: This invention relates to a method of evaluating a squeegeeing property of powder for lamination shaping by stable criteria. In this method, the squeegeeing property is evaluated using at least a satellite adhesion ratio of the powder and an apparent density of the powder. The satellite adhesion ratio is the ratio of the number of particles on which satellites are adhered to the number of all particles. If the satellite adhesion ratio is equal to or less than 50%, and the apparent density is equal to or more than 3.5 g/cm3, the squeegeeing property is evaluated as that the powder can be spread into a uniform powder layer in the lamination shaping. Furthermore, if the 50% particle size of a powder obtained by a laser diffraction method is 3 to 250 ?m, the squeegeeing property is evaluated as that the powder can be spread into a uniform powder layer in the lamination shaping.

Abstract: In this invention, a copper powder to which phosphorus (P) is added is developed such that a high-density laminated and shaped product can be obtained by a laminating and shaping method using a fiber laser as a heat source by appropriately reducing the electrical conductivity of copper, so a laminated and shaped product having a high density and a high electrical conductivity can be obtained. This invention is a copper powder for lamination shaping in which a phosphorus element is added to pure copper. The copper powder desirably contains 0.01 wt % or more of the phosphorus element. The copper powder more desirably contains 0.04 wt % or more of the phosphorus element. The copper powder desirably contains 0.30 wt % or less of the phosphorus element. The copper powder more desirably contains 0.24 wt % or less of the phosphorus element. No element other than the phosphorus element is desirably added to the copper powder.

Abstract: This invention provides a copper powder to which tin (Sn) is added such that a high-density laminated and shaped product can be obtained by a laminating and shaping method using a fiber laser as a heat source by appropriately reducing the electrical conductivity of copper, so a laminated and shaped product having a high density and a high electrical conductivity can be obtained. That is, this invention provides a copper powder for lamination shaping in which a tin element is added to pure copper. Desirably, the copper powder contains 0.5 wt % or more of the tin element. More desirably, the copper powder contains 5.0 wt % or more of the tin element. When the product has an electrical conductivity sufficient as a copper product, the copper powder desirably contains 6.0 wt % or less of the tin element. Furthermore, no element other than the tin element is desirably added to the copper powder.

Abstract: The present invention relates to a metal powder which shortens a lamination-shaping time and facilitates the removal of an unnecessary powder after lamination-shaping by decreasing a pre-sintering temperature by using a processed metal powder. This metal powder for lamination-shaping is obtained by coating the surface of a powder of a nickel-based alloy with a conductive material. When the powder is the powder of the nickel-based alloy containing nickel as a main component and chromium and iron as primary subcomponents, the powder is coated, e.g., plated with nickel as the conductive material. The particle diameter range of the powder of the nickel-based alloy is 10 to 200 ?m, preferably 25 to 150 ?m, and more preferably 45 to 105 ?m. The thickness range of the conductive material is 0.1 to 1 ?m, and preferably 0.3 ?m or more.

Abstract: The weld seam tracking and the welding torch height are controlled, the waveform of the welding voltage or the welding current of the arc is detected, the waveform of the above-described welding voltage or welding current under an appropriate welding condition to a reference gap G.sub.ref is stored as a reference waveform, the area .vertline..DELTA.SG.vertline. of a deviation part of the detected waveform to the above-described reference waveform is obtained, .DELTA.SG is obtained by judging the positive and negative of .vertline..DELTA.SG.vertline., the relationship between the value of .DELTA.SG and the root gap G is experimentally determined in advance, and the root gap G is calculated from the value of .DELTA.SG.

Abstract: A lattice welding robot detects an X-axis slide position of X.sub.p by an arc sensor of a welding torch, compares the value of X.sub.p with a reference value of X.sub.0 by a comparator, calculates a differential value of the value of X.sub.p by a differentiator and computes a travel speed correction amount .DELTA.V from a difference between a comparator output value and a differentiator output value by a computing unit. The correction amount .DELTA.V is added to an initial speed of each of inside wheels and outside wheels of a welding carriage to control each of driving motors for the inside wheels and the outside wheels by an adding speed command V.sub.in and an adding speed command V.sub.out, respectively. Thereby, a rough guidance for the welding carriage to trace a weld line is performed.

Abstract: A method for one-side root path welding of a pipe joint comprises the steps of forming a ring groove having a V-shaped bottom portion thereof at end faces of both pipes whose joint is circumferentially welded, attaching a backing material to a butt portion of the pipes from an internal side of the pipes, running an automatic welding machine along a guide rail mounted on an outer surface of the pipes in the circumferential direction thereof, controlling a position of a welding torch along a seam by means of an arc sensor, and welding root pass from the outer side of the pipes with a predetermined welding current and at a welding speed in a high-speed rotating arc welding of the pipes at a predetermined rotational speed and with a predetermined diameter of rotation. The rotational speed of arc is from 10 to 150 Hz. The rotation diameter of the arc is from 1 to 4 mm. The welding current is from 200 to 500 A. The welding speed is from 75 to 300 cm/min.

Abstract: An apparatus for detecting a shape of a groove, comprises: a device for forming picture images of a groove and a groove face of a work piece of metal to be welded with the use of a welding arc as illuminating light; a storage device for storing information on picture elements of the picture images formed by the device for forming picture images; an integrating device for integrating the information of the picture elements stored in the storage device in a predetermined direction of a memory in the storage device; a differentiating device for differentiating the integrated information in the direction rectangular to the predetermined direction of the memory; and a detecting device for detecting information of shapes of the groove and the groove face on the basis of the differentiated information on the picture elements.

Abstract: This invention relates to a rotational arc welding machine that gives a rotational circular motion to arc generated from an electrode. The machine supports rotatably an electrode (20) at a predetermined distance (d) from the center of a disc (25) which makes a rotational circular motion and at the same time supports said electrode at the upper part thereof as the supporting point therefor, causing the arc generated from said electrode to make a rotational circular motion by rotating said disc. Accordingly, in the said machine, even though the lower part of the electrode makes a circular motion, the electrode itself does not rotate; therefore, electricity can be directly supplied to the electrode.

Abstract: The present invention provides a method of efficiently and stably manufacturing a high-purity metal powder of a desired particle size, which is used for powder metallurgy or the like, by generating arc 18 between electrodes 12 and 13 to melt the distal end portions of the electrodes, causing droplets 19 of the molten metal to drop onto rotating disk 14, scattering the dropped droplets by a centrifugal force, thereby cooling the droplets, and an apparatus for the same.

Abstract: A method for controlling a penetration bead, in an automatic one-side gas shielded arc welding wherein the backing material is adhered to the back of work pieces along a weld line and the welding is effected automatically from the surface side of the work pieces, comprises: putting an electrically conductive material on the surface of the backing material in the longitudinal direction; detecting a voltage between the work pieces and the electrically conductive material during the welding and controlling the voltage to be a predetermined reference voltage. The voltage is controlled by comparing the reference voltage and the detected voltage to obtain their difference and by correcting a speed of a travelling carriage which corresponds to the difference voltage to let the detected voltage be equal to the reference voltage. The electrically conductive material is one selected from a metallic foil tape, a metallic net and a wire.

Abstract: An apparatus for automatically welding a cylindrical vessel, which comprises: a rotating means (8) for rotating a cylindrical vessel to be welded around the center axis thereof; a travelling carriage (1); a manipulator (2) mounted on the carriage (1), said manipulator comprising a vertical post (10) secured onto the carriage (1), a horizontal column (11) movable horizontally and vertically along the vertical post (10), and an expansion arm (12) fitted rotatably to the leading end of the horizontal column (11); a welding head (4) fitted through an L-shaped fitting member (3) to the tip of the arm (12), said welding head comprising a welding nozzle (16), a groove profiling means (17) and a groove shooting means (20); a welding wire feeder (5) mounted on the carriage (1); a welding electric power source (6) mounted on the carriage (1); and a welding controller (9) mounted on the carriage (1), said welding controller comprising an image processor (32), a welding current controller (33), a welding wire feed contro

Abstract: There is disclosed a method for arc welding wherein an electrode wire is rotated to produce an arc rotating at an elevated speed and wherein the arc produced in this manner is used as an arc sensor for making a bevel profiling. According to the invention, the rotational speed of the arc N is set so as to be larger than a constant speed as determined by the time constant of the change of the wire melting speed so that the difference between the welding current when the electrode wire is at the center of the bevel and that when the electrode wire is at the extreme lateral position is increased to improve the bevel profing performance.