The present invention relates to a method for welding a half coil of a reactor, which performs the gas metal arc welding (GMAW) along a half coil temporarily welded to a welding machine body using an automatic welding machine to increase a formation amount of back beads, thereby increasing coupling strength of the half coil, increasing airtightness of a fluid flowing along the half coil, securing uniform welding quality by automatic welding, increasing productivity, and reducing production costs.

Described herein is an aluminium alloy multi-layered brazing sheet product for brazing in an inert-gas atmosphere without a flux that includes a core layer made of a 3xxx alloy that includes <0.2 wt.% Mg, and that provides a covering clad layer that includes 2-6 wt.% Si on one or both sides of said 3xxx alloy core layer and a Al—Si brazing clad layer that includes 7-13 wt.% Si positioned between the 3xxx alloy core layer and the covering clad layer, wherein the covering clad layer has a thickness X.sub.1 and the Al—Si brazing clad layer has a thickness X.sub.2 and wherein X.sub.2 ≥ 2X.sub.1. Also described herein is the use of an aluminium alloy multi-layered brazing sheet product in a flux-free controlled atmosphere brazing (CAB) operation to produce a heat exchanger apparatus.

The invention relates to a method for additive manufacture of a workpiece under protective gas, wherein a workpiece is assembled from a sequence of workpiece contours, each of which is manufactured by selective sintering or melting of a powdery or wire-like material by applying an energy beam thereto, wherein a workpiece contour is manufactured under the effect of a protective gas consisting of carbon dioxide and an inert gas. According to the invention, the chemical composition of each workpiece contour is modified according to a specified program by variation of the composition of the protective gas. Heat treatment occurring after manufacture of the workpiece contour provides for defined mechanical and technological quality values of the workpiece contour. A workpiece having zones with defined mechanical and technological quality values is produced in this manner.

Provided is a solid wire for gas metal arc welding, solid wire being suitable as a welding material for high-Mn steel materials and generating less fume during welding. The solid wire of the present invention has a composition containing, in mass %, C: 0.20 to 0.80%, Si: 0.15 to 0.90%, Mn: 15.0 to 30.0%, P: 0.030% or less, S: 0.030% or less, Al: 0.020% or less, Ni: 0.01 to 10.00%, Cr: 6.0 to 15.0%, Mo: 0.01 to 3.50%, O: 0.010% or less, N: 0.120% or less, and the balance being Fe and incidental impurities.

Laser cutting on a plated steel sheet is executed by cutting the plated steel sheet by irradiating the plated steel sheet covered with a plate metal with laser light at a wavelength in a 1 micrometer band; and emitting assist gas onto a cut surface of the plated steel sheet, the cut surface being formed in the step of cutting, to make the plate metal fused by irradiation of the laser light flow to the cut surface so as to cover the cut surface with the plate metal.

The invention relates to a method for producing a metal-ceramic substrate and to a furnace suitable for carrying out the method. With the method, a metal-ceramic substrate with increased thermal and current conductivity can be obtained. The method comprises the steps of providing a stack containing a ceramic body, a metal foil, and a solder material in contact with the ceramic body and the metal foil, the solder material comprising a metal having a melting point of at least 700° C., a metal having a melting point of less than 700° C., and an active metal, and heating the stack, the stack passing through a heating zone for heating.

A MIG welding method for carbon steels using an Ar shielding gas. The method includes short-circuiting a welding wire and a base material. The average short-circuiting frequency in welding is 20 Hz to 300 Hz and the maximum short-circuiting period is 1.5 s or less.

A three-dimensional (3D) metal object manufacturing apparatus is configured to increase the oxidation of ejected melted metal drops for the formation of metal support structures during manufacture of a metal object with the apparatus. The oxidation can be increased by either increasing a distance between the ejector head and a platform supporting the metal object or by providing an air flow transverse to the direction of movement of the melted metal drops, or both.

A flux-cored wire comprising a flux which is a core and a hoop which is an outer skin or sheath is described. The flux includes a strong deoxidizing metal element containing Mg and Al, and a fluoride powder. At least 60 mass % of a strong deoxidizing metal powder related to the strong deoxidizing metal element has a grain size of at most 150 μm. At least 60 mass % of the fluoride powder has a grain size of at most 75 μm. The flux is present at a concentration of 10-30 mass % relative to a total mass of the flux-cored wire. The flux-cored wire also requires a specific composition of elements.

An austenitic stainless steel flux cored wire may provide a welded metal having excellent cryogenic temperature toughness; a welded metal from the wire may have excellent cryogenic temperature toughness; and a welding method may involve such wire(s). An austenitic stainless steel flux cored wire in which a flux is filled in a steel-made shell. The flux cored wire may contain Si, Mn, Ni, Cr, C, P, and N in amounts each falling within a specified range relative to the entire mass of the wire, with the remainder made up by Fe and unavoidable impurities, and X.sub.1 is 17.5 to 22.0 inclusive, as calculated by formula (1):

X.sub.1=[Ni].sub.W+0.5×[Cr].sub.W+1.6×[Mn].sub.W+0.5×[Si].sub.W+15×[C].sub.W  (1),

wherein, in formula (1), [Ni].sub.W, [Cr].sub.W, [Mn].sub.W, [Si].sub.W and [C].sub.W represent the contents (% by mass) of Ni, Cr, Mn, Si, and C, relative to the entire mass of the wire.