Abstract: Tombstoning susceptibility and reflow peak temperature reduction of solder alloys, in particularly lead-free solder alloys, has been found to be achieved effectively by mixing the solder alloy in the form of an alloy paste with a low melting alloy utilised in powder form, in particular a Bi-containing alloy.

Abstract: To avoid the use of harmful CFCs in the cleaning of soldered printed circuit board assemblies, their manufacture is accomplished using a screen-printable solder paste composition which will in use yield minimal flux residues which will not require removal by a solvent cleaning step. The paste composition is formulated by incorporating the powdered soft solder alloy in a liquid medium containing up to 10% by weight of a non-corrosive organic flux material, a substantially water-immiscible organic solvent, and one or more thickening agents.

Abstract: In order to avoid the undesirable formation of flux residues when soldering electronic components, as in the production of printed circuit assemblies, there is used, as the solvent for a non-corrosive flux material, a mixture composed of a major proportion by weight of a monohydric alcohol and a minor proportion by weight of a water-immiscible polyalkylene glycol dialkyl or diaryl ether.

Abstract: Solder baths for use in the electronics industry are formed by converting into a molten condition a soft solder material in the form of an extruded bar of soft solder alloy having one or more cores composed of (I) esters of polyhydric alcohols of molecular weight of at least 300, (II) ester derivatives of rosin or modified rosin, (III) hydrocarbon resins, and/or (IV) polymeric waxes, so that the resulting solder bath is provided with a layer of anti-oxidant material derived from the cores which assists in preventing formation of oxide impurity on the surface of the molten solder bath and which may also act as a solder flux, thereby obviating the conventional necessity of applying a separate antioxidant material to the surface of the bath and of using a separate solder flux.

Abstract: A portable wire dispenser, suitable for use with solder wire of the type employed in making soldered joints in electrical equipment by a soft soldering operation, comprises a cylindrical body one end of which is closed and the other end of which is open and accommodates an outlet formed with a helical first passageway in communication with a second passageway which is substantially parallel to the longitudinal axis of the cylindrical body, the arrangement being such that a helical coil of wire can be contained in the cylindrical body and can be drawn therefrom by means of a free end of wire emerging from the second passageway in the outlet but is constrained from slipping back into the cylindrical body by the helical first passageway which meets the second passageway at approximately a right angle.

Abstract: Soft solder in the form of an extruded or cast bar or ingot is provided with a coating which prevents formation of surface oxide during storage of the bar or ingot and which acts as an anti-oxidant surface layer when the bar or ingot is used to form a molten solder bath. The coating may also act as a solder flux so that when a solder bath is formed from the soft solder bar or ingot, the anti-oxidant surface layer formed from the coating also acts as a flux composition hence obviating the necessity of employing a separate solder flux in a soldering operation in which the molten solder bath is used. The coating is formed from a coating material essentially comprising a mixture of a neutral ester of a polyhydric alcohol and an ester derivative of rosin or of a modified rosin.

Abstract: The soft soldering of an aluminium or aluminium-based alloy member to another member of a metal or alloy capable of being soft soldered to aluminium at a joint site is effected using a lead/tin soft solder alloy in conjunction with a flux containing as one of the essential constituents a silver halide so that sufficient silver is deposited with the soft solder alloy at the joint site to prevent corrosion of the joint.

Abstract: Flux compositions for use in soft soldering processes comprise as part or all of the active flux material at least one compound selected from the class of compounds characterized by the presence therein of a perhydro-1,2-cyclopentanophenanthrene ring system. Compounds belonging to this class include the bile acids.

Abstract: There is described a method of soft soldering aluminium or alloys thereof using a fluxed solder composition. The fluxed solder composition comprises a soldering flux suitable for use in soft soldering aluminium and its alloys and a soft solder alloy of lead, tin and silver and, optionally, up to 3% copper. The composition of the soft solder alloy is such that it contains at least 35% lead and 10% tin, and x% silver wherein x=0.1+(5.times.10.sup.-4)(Sn).sup.2 +(1.times.10.sup.-5)(Sn).sup.3, (Sn) being the percentage by weight of tin in the alloy.

Abstract: A flux composition of the non-corrosive type suitable for use in soft soldering, particularly in the electrical and electronics industries, contains in place of the conventional natural rosin (colophony), an ester of a polyhydric alcohol such as pentaerythritol tetrabenzoate. The composition can be in solid or liquid form and in the latter can perform the multiple functions of an etch resist, a protective coating and a flux in the production of printed circuit assemblies.

Abstract: There is described a composition for soft soldering aluminium or alloys thereof using a fluxed solder composition. The fluxed solder composition comprises a soldering flux suitable for use in soft soldering aluminium and its alloys and a soft solder alloy of lead, tin and silver and, optionally, up to 3% copper.

Abstract: A flux composition of the non-corrosive type suitable for use in soft soldering, particularly in the electrical and electronics industries, contains in place of the conventional natural rosin (colophony), an ester of a polyhydric alcohol such as pentaerythritol tetrabenzoate. The composition can be in solid or liquid form and in the latter can perform the multiple functions of an etch resist, a protective coating and a flux in the production of printed circuit assemblies.