A method of making pre-sintered preforms using a mixture of base superalloy particles and titanium-containing boron and silicon free braze alloy particles, such as for the repair of superalloy gas turbine engine components. Alloy particles as large as 2 mm provide reduced shrinkage when compared to prior art preforms. Braze material compositions disclosed herein are boron and silicon free and may have melting temperature ranges as low as 10 C., and they include no element not already present in the composition of the superalloy component.

A system for producing chemicals, such as, ethylene or gasoline, at high temperature (above 1100 degrees C.) having a feedstock source. The system includes a chemical conversion portion connected with the feedstock source to receive feedstock and convert the feedstock to ethylene or gasoline. The conversion portion includes a coil array and a furnace that heats the feedstock to temperatures in excess of 1100 C. or 1200 C. or even 1250 C. or even 1300 C. or even 1400 C. A method for producing chemicals, such as ethylene or gasoline, at high temperature.

A resistive welding electrode includes at least a weld face constructed of a refractory-based material that exhibits an electrical conductivity that is less than or equal to 65% of the electrical conductivity of commercially pure annealed copper as defined by the International Annealed Copper Standard (IACS). A method of using the resistive welding electrode to resistance spot weld a workpiece stack-up that includes an aluminum alloy workpiece and steel workpiece that overlap and contact each other at a faying interface is also disclosed.

A resistive welding electrode includes at least a weld face constructed of a refractory-based material that exhibits an electrical conductivity that is less than or equal to 65% of the electrical conductivity of commercially pure annealed copper as defined by the International Annealed Copper Standard (IACS). A method of using the resistive welding electrode to resistance spot weld a workpiece stack-up that includes an aluminum alloy workpiece and steel workpiece that overlap and contact each other at a faying interface is also disclosed.

A method of manufacturing includes depositing a braze filler adjacent to a void between a first component and a second component thus holding the components in position before brazing. The first and second components are heated to melt and flow the braze filler into the void. A braze joint is formed between the first and second components by cooling the braze filler. Depositing the braze filler can include laser cladding the braze filler to the first and/or second components adjacent the void. The method also optionally includes welding the first and second components in position with the braze filler adjacent to the void. The braze filler may be deposited as a powder, cold spray, melted brazed filament, spherical ball or any other suitable form.

A method of manufacturing includes depositing a braze filler adjacent to a void between a first component and a second component thus holding the components in position before brazing. The first and second components are heated to melt and flow the braze filler into the void. A braze joint is formed between the first and second components by cooling the braze filler. Depositing the braze filler can include laser cladding the braze filler to the first and/or second components adjacent the void. The method also optionally includes welding the first and second components in position with the braze filler adjacent to the void. The braze filler may be deposited as a powder, cold spray, melted brazed filament, spherical ball or any other suitable form.

A method for joining heat transfer plates, comprising: applying a melting depressant composition on individual application areas of a first metal sheet, each application area comprising a mid-section and two end-sections; pressing ridges and grooves in the metal sheet, the ridges extending in a direction that extends between the end-sections of the application areas, such that the application areas are located on top of the ridges; bringing the metal sheet into contact with a second, pressed metal sheet, such that contact points are formed where the mid-sections of the application areas relocated; heating the sheets until melted metal is formed at the application areas where the melting depressant composition is applied; and allowing the melted metal to solidify such that a joint is obtained at the contact points.

Embodiments of hardfacing layers in which wear resistant particles are substantially uniformly distributed in a matrix material are provided. The composition and microstructure of the matrix material and the amount, size and distribution of the wear resistant particles can be such that the hardfacing is wear resistant but still retains some toughness. The matrix material may include two components, a first component including iron, chromium and nickel and a second component including chromium and a substantial amount of carbon. The combination of the two components provides hardness and toughness to the matrix material. In embodiments of the disclosure, the wear resistant particles include tungsten. A hardfaced article, in one embodiment, may be formed by fusion welding an austenitic stainless steel filler metal to the surface of a base metal, thereby generating a weld pool; and adding a plurality of particles including tungsten carbide to the weld pool.

A braze alloy composition for sealing a ceramic component to a metal component in an electrochemical cell is presented. The braze alloy composition includes copper, nickel, and an active metal element. The braze alloy includes nickel in an amount less than about 30 weight percent, and the active metal element in an amount less than about 10 weight percent. An electrochemical cell using the braze alloy for sealing a ceramic component to a metal component in the cell is also provided.

A joined body 20 includes a porous ceramic 22 made of porous ceramic, a metal member 24 made of a metal, and a joint 30 formed of an oxide ceramic that penetrates into pores 23 of the porous ceramic 22 and joins the porous ceramic 22 to the metal member 24. The penetration depth of the oxide ceramic into the pores of the porous ceramic is preferably 10 m or more, and more preferably 15 to 50 m. The joined body 20 may be produced through a joining step of forming a joint by placing a metal raw material between a porous ceramic and a metal member and firing the metal raw material in the air at a temperature in the range of 400 C. to 900 C., where an oxide ceramic produced by oxidation of the metal raw material penetrates into the pores of the porous ceramic in the joint.