Abstract: The thermal expansion of parts to be welded to each other is reduced in that one or more of the parts are modified to include expansion slots in the welding area. This limits thermal expansion to the remaining small areas only which are allowed to expand within the slots. Total expansion of such welded parts is thus reduced after solidfication. In most applications, such slots do not effect the total design of the welded parts. If required, such slots can be sealed after welding.

Abstract: A process for treating the surface of solid fusible solder supported on a substrate, comprises a heated tool having a treatment surface with a selected shape. The heated tool is brought into contact with the solder for fusing the solder to reshape the surface of the solder. The tool is allowed to cool to permit the solder to resolidify, and when withdrawn from the solder, leaving the imprinted shape. The treatment surface is made of material which is not wettable by the solder. Stops may be utilized for limiting movement between the tool and the substrate to a specified gap for the treatment surface.

Abstract: A process for joining the surface of one preferably metallic member to another at a joint, and using solder to create the joint at a joining temperature, includes applying a medium to the joint which evaporates by microexplosion at below the joining temperature. The microexplosive evaporation of the medium advantageously cleans the surfaces of the members and reduces surface tension to allow solder to flow and wet the surfaces. The medium is advantageously glycerin or a mixture of glycerin and detergent so that no residue remains after the joining operation.

Abstract: An apparatus for connecting one object to another by heating the objects comprises a heated tool having a heater bar with a heating surface for contacting one of the objects. The tool can be moved with pressure against one of the objects for heating the objects. One or more nozzles are provided for directing heated gas in a flow either against the heater bar or against one of the objects for better controlling the heat transfer to the objects.

Abstract: A heating tool for heating at least one object, comprises an electrically heated U-shaped heater bar having a heat supplying contact surface for being pressed into contact with the object to be heated. A radiator is advantageously connected between arms of the U-shaped heater bar for receiving electrical current to produce radiated heat which heats another portion of the object or another object. Electricity may be provided by a single source to both the contact surface and the radiator.

Abstract: A heated tool for soldering objects to a plurality of pads which are spaced apart by a selected pitch, comprises a tool member having a heating surface with a plurality of spacer bars thereon, spaced by the pitch between the pads. The spacer bars act to separate one pad from the other to avoid the flow of solder between the pads.