Copper-manganese alloy brazing pastes can be substantially improved by the inclusion of a minor amount of silicon in the alloy. The brazing alloy can contain by weight between about 0.5% and 3% silicon to provide a brazing composition for brazing at temperatures between about 1650.degree. C. and 1850.degree. C.

Spherical solder drops having precise and accurate shape are formed by an ejection device and solidified to form solder balls for making solder pastes. The diameters of the solidified solder balls are determined by an excitation signal applied to the ejection device and changes in the diameter of the orifice in the ejection device. A solder paste is produced by mixing solidified solder balls of a single diameter or a combination of several different diameters with a carrier.

A conductive copper paste composition is adapted to yield a highly conductive film receptive to solders without pretreatment. This conductive paste comprises a copper metal powder, a resin component including a thermosetting resin, and an assortment of additives. In use, the paste is applied to an insulation substrate to a predetermined circuit pattern and cured in situ. Soldering can then be performed directly on the cured circuit. This contributes not only to the conductivity of the circuit but dispenses with the activation treatment and electroless plating or electroplating that have heretofore been essential prior to soldering. The invention, therefore, results in a substantial curtailment of production process and a proportional economic advantage. In addition, this conductive paste can be used in such applications as electrode and through-hole connections, formation of electromagnetic and electrostatic shield layers, and so on in the manufacture and assembly of electronic components and circuits.

A solder powder comprises solder particles having a distribution such that the number of particles having a particle diameter of 20 .mu.m or less is 30% or less, wherein the oxygen content is 500 ppm or less. A flux for solder paste comprises an organic acid component consisting of an organic acid ester and an ester decomposer catalyst, an organic halogen compound, a reducing agent and a resin component. A solder paste mainly comprises a flux and a solder powder, wherein the water content of the solder paste is 0.5% by weight or less.

A method for producing a copper brazed hose coupling assembly from a plurality of members in which one of the members is electroplated with copper is provided. A stem member is press fitted to a collet member and subsequently brazed together in a furnace. The copper material being located adjacent the joint between the stem and collet members results in a high quality braze joint to be provided with a predetermined minimum amount of copper. The copper brazed hose coupling is particularly suited for use in a fluid operated system.