A tubular welding electrode for arc welding that has improved crack resistance comprises a steel sheath disposed around a granular powder flux fill core. The granular powder flux fill core comprises magnesium oxide and a sulfur source such as iron sulfide.

A composition for use in an electronic assembly process, the composition comprising a filler dispersed in an organic medium, wherein: the organic medium comprises a polymer; the filler comprises one or more of graphene, functionalized graphene, graphene oxide, a polyhedral oligomeric silsesquioxane, graphite, a 2D material, aluminum oxide, zinc oxide, aluminum nitride, boron nitride, silver, nano fibers, carbon fibers, diamond, carbon nanotubes, silicon dioxide and metal-coated particles, and the composition comprises from 0.001 to 40 wt. % of the filler based on the total weight of the composition.

A welding system includes a welding power source configured to provide pulsed electropositive direct current (DCEP), a gas supply system configured to provide a shielding gas flow that is at least 90% argon (Ar), a welding wire feeder configured to provide tubular welding wire. The DCEP, the tubular welding wire, and the shielding gas flow are combined to form a weld deposit on a zinc-coated workpiece, wherein less than approximately 10 wt % of the tubular welding wire is converted to spatter while forming the weld deposit on the zinc-coated workpiece.

A method for joining engine components includes positioning a first plurality of thermal protection structures across a thermal protection space between a first thermal protection surface and a second thermal protection surface. The first and second engine components are locally joined by forming a first plurality of transient liquid phase (TLP) or partial transient liquid phase (PTLP) bonds along corresponding ones of the first plurality of thermal protection structures between the first thermal protection surface and the second thermal protection surface. The second thermal protection surface is formed from a second surface material different from a first surface material of the first thermal protection surface.

The Cu core ball contains a Cu ball and one or more metal layer for covering a surface of the Cu ball, each layer including one or more element selected from Ni, Co, Fe and Pd. The Cu ball contains at least one element selected from Fe, Ag, and Ni in a total amount of 5.0 or more to 50.0 ppm by mass or lower, S in an amount of 0 ppm by mass or more to 1.0 ppm by mass or lower, P in an amount of 0 ppm by mass or more to less than 3.0 ppm by mass, and remainder of Cu and inevitable impurities. The Cu ball contains purity which is 99.995% by mass or higher and 99.9995% or lower, sphericity which is 0.95 or higher and a diameter of 1 m or more to 1000 m or lower.

A process for brazing of aluminium magnesium alloys is described applying a flux which comprises KAlF.sub.4 or CsAlF.sub.4 or both as major constituent. The flux further comprises at least one alkaline or alkaline earth metal compound selected from the group consisting of KAlF.sub.4, CsAlF.sub.4, Li.sub.3AlF.sub.6, CaF.sub.2, CaCO.sub.3, MgF.sub.2, MgCO.sub.3, SrF.sub.2, SrCO.sub.3, BaF.sub.2, and BaCO.sub.3. Preferably the flux comprises or consists of KAlF.sub.4, CsAlF.sub.4, and Li.sub.3AlF.sub.6 and optionally contains also BaF.sub.2.

Disclosed are a composition for brazing aluminum, and a method for brazing aluminum using the same. The composition for brazing aluminum may have excellent adhesion or bonding strength and improved corrosion resistance, for example, after bonding. The composition for brazing aluminum may include an amount of about 30 to 60 parts by weight of a zinc-based compound, and an amount of about 10 to 40 parts by weight of a metal titanium. For example, by using the composition for brazing aluminum in, base metals may be bonded by applying and heat treating the flux without addition of separate filler metal, thereby simplifying a bonding process and reducing a bonding time.

According to an aspect of the present invention, there is provided a flux-cored wire including a steel sheath and a flux that fills the steel sheath. The flux contains fluorides of which a total value a of F-equivalent values is 0.21% or more, oxides of which the total value of amounts ranges from 0.30% to less than 3.50%, and carbonates of which a total value of amounts ranges from 0% to 3.50%. An amount of CaO ranges from 0% to less than 0.20%. An amount of iron powder ranges from 0% to less than 10.0%. A X-value is 5.0% or less. The amount of CaF.sub.2 is less than 0.50%. The amount of Ti oxides ranges from 0.10% to less than 2.50%. A ratio of to ranges from 0.10 to 4.00. A total value of amounts of MgCO.sub.3, Na.sub.2CO.sub.3, and LiCO.sub.3 ranges from 0% to 3.00%. Other chemical composition is within a predetermined range. Ceq ranges from 0.45% to 1.20%.

A process for brazing of aluminium magnesium alloys is described applying a flux which comprises KAlF.sub.4 or CsAlF.sub.4 or both as major constituent. The flux further comprises at least one alkaline or alkaline earth metal compound selected from the group consisting of KAlF.sub.4, CsAlF.sub.4, Li.sub.3AlF.sub.6, CaF.sub.2, CaCO.sub.3, MgF.sub.2, MgCO.sub.3, SrF.sub.2, SrCO.sub.3, BaF.sub.2, and BaCO.sub.3. Preferably the flux comprises or consists of KAlF.sub.4, CsAlF.sub.4, and Li.sub.3AlF.sub.6 and optionally contains also BaF.sub.2.

A welding system includes a welding power source configured to provide pulsed electropositive direct current (DCEP), a gas supply system configured to provide a shielding gas flow that is at least 90% argon (Ar), a welding wire feeder configured to provide tubular welding wire. The DCEP, the tubular welding wire, and the shielding gas flow are combined to form a weld deposit on a zinc-coated workpiece, wherein less than approximately 10 wt % of the tubular welding wire is converted to spatter while forming the weld deposit on the zinc-coated workpiece.