The purpose of the present invention is to provide, as a wire rod suitable for use as a substance for welding materials and, in particular, for welding rods, a wire rod for welding rods, having high tensile strength at room temperature and excellent drawing characteristics, and a manufacturing method therefor.

Ni—Mn—Si based braze filler alloys or metals which may be nickel-rich, manganese-rich, or silicon-rich braze filler alloys, have unexpectedly narrow melting temperature ranges, low solidus and low liquidus temperatures, as determined by Differential Scanning calorimetry (DSC), while exhibiting good wetting, and spreading, without deleterious significant boride formation into the base metal, and can be brazed at lower temperatures. The nickel rich alloys contain 58 wt % to 70 wt % nickel, the manganese-rich alloys contain 55 wt % to 62 wt % manganese, and the silicon-rich alloys contain 25 wt % to 29 wt % silicon. Copper with or without boron to partly replace nickel may be employed without any substantial increase of the melting point, or to reduce the melting point. The braze filler alloys have sufficient brazability to withstand high temperature conditions for thin-walled aeronautical and other heat exchangers.

The present disclosure is directed to a tubular welding electrode with a sheath encapsulating a flux core, where the sheath comprises a number of added pores. The added pores may provide escape paths for the outgassing of moisture and hydrocarbons from the flux core when the tubular welding electrode is baked. In addition, the added pores may be used to hold a liquid, such as a lubricant. The added pores may be introduced using a process such as laser drilling or chemical etching, and may be added to a strip of sheath material prior to forming the strip into a tubular welding electrode.

A method of attaching a first metal object to a second metal object is presented. The first metal object and the second metal object are dissimilar materials. The first metal object comprises an upper surface and a lower surface. The method comprises: positioning the first metal object in intimate contact with the second metal object such that the second metal object is in contact with the lower surface of the first metal object; identifying at least one attachment location on the upper surface of the first metal object where the first metal object is in intimate contact with the second metal object; adding a powdered metal on the upper surface of the first metal object at the at least one attachment location; and firing a heat source at the powdered metal to melt the powdered metal and drive the melted powdered metal through the first metal object and into the second metal object.

A welding or additive manufacturing wire drive system includes a welding wire spool and first and second drive rolls. One or both of the drive rolls has a circumferential groove. The system includes a first welding wire, drawn from the welding wire spool, and located between the drive rolls in the circumferential groove, and a second welding wire, drawn from the welding wire spool, and located between the drive rolls in the circumferential groove. The first welding wire contacts the second welding wire between the first drive roll and the second drive roll. The first welding wire further contacts a first sidewall portion of the circumferential groove, and the second welding wire further contacts a second sidewall portion of the circumferential groove. Both of the first welding wire and the second welding wire are radially offset from a central portion of the circumferential groove.

Process for manufacturing a multilayer strip or sheet, comprising the successive steps of: casting a brazing aluminum alloy in the form of a casting slab; sawing the casting slab to obtain sawn brazing alloy layers; bonding a core aluminum alloy layer with at least one sawn brazing aluminum alloy layer to obtain a multilayer assembly; preheating the multilayer assembly; hot-rolling the multilayer assembly to obtain a multilayer strip or sheet, the first hot-rolling pass inducing a reduction in thickness of the multilayer assembly greater than or equal to 0.5% of the thickness of the multilayer assembly before said hot-rolling pass.

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.

Undercooled liquid metallic core-shell particles, whose core is stable against solidification at ambient conditions, i.e. under near ambient temperature and pressure conditions, are used to join or repair metallic non-particulate components. The undercooled-shell particles in the form of nano-size or micro-size particles comprise an undercooled stable liquid metallic core encapsulated inside an outer shell, which can comprise an oxide or other stabilizer shell typically formed in-situ on the undercooled liquid metallic core. The shell is ruptured to release the liquid phase core material to join or repair a component(s).

A microelectronic device has bump bond structures on input/output (I/O) pads. The bump bond structures include copper-containing pillars, a barrier layer including cobalt and zinc on the copper-containing pillars, and tin-containing solder on the barrier layer. The barrier layer includes 0.1 weight percent to 50 weight percent cobalt and an amount of zinc equivalent to a layer of pure zinc 0.05 microns to 0.5 microns thick. A lead frame has a copper-containing member with a similar barrier layer in an area for a solder joint. Methods of forming the microelectronic device are disclosed.

A solder alloy is provided which suppresses the change in a solder paste over time, decreases the temperature difference between the liquidus-line temperature and the solidus temperature, and exhibits a high reliability. The solder alloy has an alloy constitution composed of: 10 ppm by mass or more and less than 25 ppm by mass of As; at least one selected from the group consisting of 0 ppm by mass to 10000 ppm by mass of Bi and 0 ppm by mass to 5100 ppm by mass of Pb; more than 0 ppm by mass and no more than 3000 ppm by mass of Sb; and a remaining amount of Sn; and satisfies both the formula (1) and the formula (2).
300≤3As+Sb+Bi+Pb  (1)
0.1≤{(3As+Sb)/(Bi+Pb)}×100≤200  (2) In the formula (1) and the formula (2), As, Sb, Bi, and Pb each represents an amount thereof (ppm by mass) in the alloy constitution.