Abstract: A self-contained crucible assembly for forming a weld between a pair of metal articles, includes a container with side walls and a fusible bottom, a refractory material lining the side walls, an exothermic weld material within the container, an ignitor partially within or close to the weld material and partially external to the container, and a cover sealing the weld material. The ignitor may be stiffened to maintain its shape, and keep it in a desired position relative to the exothermic weld material. The crucible assembly is configured to be placed on mold having a chamber therein. Upon ignition of the weld material via actuation of the ignitor, the weld material reacts exothermically to produce molten weld metal and slag. The fusible bottom of the container is melted by the liquified molten metal, and the weld material flows into a weld chamber of the mold to produce the weld.

Abstract: An ignitable solid material includes molten-metal-producing materials, as well as other materials for retaining its shape when ignited. The molten-metal-producing materials may include a metal-producing reaction mixture, for example including a reaction mixture comprising a reducing agent and a metal compound powder. The other materials may include a binder, and a heat-retaining material, such as sand. The ingredients of the ignitable solid material may be pressed together and dried, to produce a solid, machinable, heat-producing material (a heat block) that may be formed in any of a variety of shapes. An insulating material, such as a ceramic blanket material, may be placed on one or more sides of the ignitable solid material, for example to direct heat produced by the reaction of the solid material in one or more desired directions. The solid material may be used in any of a variety of situations where concentrated heat is desired.

Abstract: A self-contained crucible assembly for forming a weld between a pair of metal articles, includes a container with side walls and a fusible bottom, a refractory material lining the side walls, an exothermic weld material within the container, an ignitor partially within or close to the weld material and partially external to the container, and a cover sealing the weld material. The ignitor may be stiffened to maintain its shape, and keep it in a desired position relative to the exothermic weld material. The crucible assembly is configured to be placed on mold having a chamber therein. Upon ignition of the weld material via actuation of the ignitor, the weld material reacts exothermically to produce molten weld metal and slag. The fusible bottom of the container is melted by the liquified molten metal, and the weld material flows into a weld chamber of the mold to produce the weld.

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.