Abstract: A solid weld-metal-producing material is formed by agglomerating weld metal material powder. An igniter may be integrally formed in or on the agglomerated weld metal material. In addition to typical components of a weld metal material mixture, such as a reductant metal and a transition metal oxide, the agglomerated weld metal mixture may include a binder material, such as sodium silicate. In addition to functioning as a binder to help hold the agglomerated weld metal material together, the binder material may aid in the exothermic reaction that occurs when the weld metal material is ignited. The agglomerated weld metal material may be made by mixing together a reductant metal powder, a transition metal oxide powder, and possibly a binder solution. A slurry of the components may be pressed together, for example, using a die and a ram, and then may be dried.

Abstract: A solid weld-metal-producing material is formed by agglomerating weld metal material powder. An igniter may be integrally formed in or on the agglomerated weld metal material. In addition to typical components of a weld metal material mixture, such as a reductant metal and a transition metal oxide, the agglomerated weld metal mixture may include a binder material, such as sodium silicate. In addition to functioning as a binder to help hold the agglomerated weld metal material together, the binder material may aid in the exothermic reaction that occurs when the weld metal material is ignited. The agglomerated weld metal material may be made by mixing together a reductant metal powder, a transition metal oxide powder, and possibly a binder solution. A slurry of the components may be pressed together, for example, using a die and a ram, and then may be dried.

Abstract: A welding apparatus and method characterized by an electrically activated high temperature igniter with a pair of lead wires adapted to be connected to a high energy source of current and a high resistance bridge between the leads. The bridge is coated with an ignition material comprising a mixture of fine aluminum, one or more metal oxides or oxygen containing compounds and a binder. The welding apparatus has a vessel filled with exothermic material. When the lead wires are supplied with a high energy electrical current, the lead wires cause the ignition material to ignite in turn causing the exothermic material to ignite. If the coated bridge wire is positioned above the exothermic material, the igniter will broadcast multiple points of ignition over the top of the exothermic material.

Abstract: Exothermic reaction mixtures are economically ignited remotely and electrically without the use of a low ignition starting material by creating a predetermined spark gap within a matrix of such mixture and then impressing a high energy spark across the gap through the use of a capacitor discharge circuit. The mixture is contained in a graphite or ceramic vessel or crucible and is supported over a tap hole or runner by a fusible metal disk. The material of the vessel is preferably graphite which is electrically conductive. In one form of the invention, an insulated wire with a bare tip is positioned just below the top surface of the mixture and the tip spaced a predetermined distance from the wall of the vessel. The capacitor discharge circuit is then employed to fire a high energy spark through a matrix of the material across the gap formed between the wire and vessel to initiate the reaction. In another form the spark gap may be established in a small cylindrical cartridge containing the material.