Brazing paste is a new kind of composite brazing material. It is a paste mixed with brazing powder, flux and binder to form a paste capable of being screen printed onto a substrate or applied to the workpiece via a dispenser. Compared to conventional brazing materials, brazing paste is more suited for automatic application in large quantities. Moreover, their application dosage can be reproduced with high precision. When brazing paste is used with induction brazing, flame brazing, reflow soldering and other methods, extremely high production efficiency can be achieved. At the same time, gas release of brazing flux is relatively low, and braze quality is excellent.
In brazing paste mixtures, the key component is brazing alloy powder. It represents 80%-90% of the total weight and acts as a filler metal to form the braze joint. The brazing flux component of the mixture is used to clean any oxide on the surfaces of the weldments and alloy powder. Brazing flux also enhances the wetting property and spread of the brazing alloy. Adhesive in the brazing paste mixture ensures that alloy powder and brazing flux is mixed properly to form a mixture of desired viscosity, and such a mixture is easy to dispense at the designated braze area during the dispensing process.