Powder metal pastes for brazing and soldering applications

Metal powders are used extensively as filler metals in brazing and soldering applications in a wide variety at industries. Paste is a commonly used form produced by mixing the metal powder with an appropriate binder. A paste offers a convenient means of placing the filler metal at the desired location in the joint. The selection of the filler metal depends primarily on the materials to be joined, the Joint design and the required joint strength. The binder system is chosen on the basis of the chemical composition, the desired rheology and flow properties of the paste, and dispensing equipment used. This paper presents an overview of some commercial paste products with on emphasis on the metal powders used The common metal and alloy compositions, manufacturing methods, powder characteristics, brazing and soldering parameters, and applications are described.