Systems and methods for low-manganese welding alloys are disclosed. An example arc welding consumable may comprise: less than 0.4 wt % manganese; strengthening agents selected from the group consisting of nickel, cobalt, copper, carbon, molybdenum, chromium, vanadium, silicon, and boron; and grain control agents selected from the group consisting of niobium, tantalum, titanium, zirconium, and boron. The grain control agents may comprise greater than 0.06 wt % and less than 0.6 wt % of the welding consumable. The resulting weld deposit may comprise a tensile strength greater than or equal to 70 ksi, a yield strength greater than or equal to 58 ksi, a ductility (as measured by percent elongation) of at least 22%, and a Charpy V-notch toughness greater than or equal to 20 ft-lbs at −20° F. The welding consumable may provide a manganese fume generation rate less than 0.01 grams per minute during the arc welding operation.

The present disclosure belongs to the field of materials with metal structures, and specifically relates to a preparation method for a nano-oxide dispersion strengthened steel. The method includes mixing a ferrochromium alloy, a ferrotungsten alloy, a ferroalloy containing a rare earth element, an oxygen source and a reduced iron powder to obtain a mixture; wrapping the mixture in a steel strip, and conducting drawing reducing to obtain a flux-cored wire; and conducting arc additive manufacturing on the flux-cored wire on a substrate, and then conducting heat treatment to obtain the nano-oxide particle dispersion strengthened steel.

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.

A method for producing an additively manufactured, graded composite transition joint (AM-GCTJ) includes preparing a grating or lattice pattern from a first alloy A; the grating or lattice pattern includes pores in the grating or lattice patterns. The grating pattern is built from a first end to a second end being denser on the first end than on second end, and gradually reduces density by increasing the pore size and/or reducing density of the grating or lattice pattern; adding a second alloy B powder to the second end of grating or lattice pattern. The second alloy B powder is filled towards the first end. A composite is formed of first alloy A and second alloy B powder in the AM-GCTJ. The composite is subjected to hot isotropic pressing (HIP) to densify the composite. The second alloy B is graduated from the first end to the second end O of AM-GCTJ.

A method for welding coated steel sheets, particularly steel sheets that are coated with an aluminum-silicon metallic coating layer, is provided. A configuration of two laser beams is provided, wherein the laser beams act on a weld pool that is to be formed, at least one laser beam rotates around a rotation axis so that the laser beams execute a movement relative to each other, and the laser beams are guided along a welding axis. In order to achieve a mixing of the weld pool, a defined stirring effect and a defined welding speed in relation to each other are adhered to, wherein a mathematically defined condition applies to the stirring effect.

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 flux-cored wire of the present disclosure has a steel sheath and a flux filled at an inside of the steel sheath, has a total amount of moisture by ratio with respect to a total wire mass of 300 ppm or less, has flux containing fluorides, and has an amount of the fluorides by ratio with respect to the total wire mass of, by total of values converted to F, 0.11 mass % or more and 2.50 mass % or less. If using the flux-cored wire of the present disclosure for welding, a stable weld shape can be obtained and, further, the amount of diffusible hydrogen of the weld metal can be reduced. For this reason, the flux-cored wire of the present disclosure can be suitably used for welding high strength steel such as ferrite steel.

Provided is a thermal spray wire as a thermal spray material for use in continuous arc wire thermal spraying machines, the thermal spray wire being for performing continuous and stable arc thermal spraying with sufficient electrical conductivity and at a stable voltage. The thermal spray wire includes a copper-plated coating having a thickness of from 0.3 to 1.2 μm on a surface of a rod made of stainless steel. Using the thermal spray wire allows for stable arc thermal spraying by a continuous arc thermal spraying machine including a wire feeding mechanism.

A weld structure includes a first stainless steel member and a second stainless steel member. A crevice made by welding is defined by welding an end of the first stainless steel member and a portion other than an end of the second stainless steel member. A portion close to the end of the first stainless steel member is formed as a weld metal portion by performing welding heat input on the portion close to the end of the first stainless steel member. In the crevice made by welding, a length L.sub.B from a boundary between the weld metal portion and a raw material portion to a crevice deepest portion and a crevice length L.sub.C from the crevice deepest portion to a 40 μm-width position satisfy L.sub.C<L.sub.B.

Welding wires may include a high alloy metal core comprising greater than about 10.5 percent by weight of the high alloy metal core of a component selected from aluminum, bismuth, chromium, molybdenum, chromium/molybdenum alloy, cobalt, copper, manganese, nickel, silicon, titanium, tungsten, vanadium, or a combination thereof; and a layer surrounding the high alloy metal core, the layer comprising copper or a copper alloy. Welding methods may include applying an electrical current sufficient to convert a welding wire to a molten state to produce a molten weld material, the welding wire comprising: a high alloy metal core comprising greater than about 10.5% of a component selected from aluminum, bismuth, chromium, molybdenum, chromium/molybdenum alloy, cobalt, copper, manganese, nickel, silicon, titanium, tungsten, vanadium, or a combination thereof; and a layer surrounding the high alloy metal core, the layer comprising copper or a copper alloy; and depositing the molten welding material onto a workpiece.