Brazing carbide tools used in a wide variety of solder, solder almost all can see. The largest amount of copper based solder and copper brazing, silver based solder amount increased rapidly in recent years.

Copper and copper base brazing filler metal is the most commonly used hard alloy brazing. Copper for a variety of hard alloy has good wettability, but in hydrogen reducing atmosphere or under the condition of vacuum brazing, we can get the best effect. The melting point of copper is 1083 DEG C, the brazing temperature between 1093~1149 DEG C in general. Copper solder joint shear strength is about 150MPa, joints plasticity and high, but at a temperature higher than 320 DEG C, the joint strength decreases rapidly so it is not adapt to work under high temperature. Because of high temperature copper brazing joint, the thermal stress is large, the crack tends to increase.

The melting temperature of copper based solder is lower than that of pure copper. Commonly used in copper base solder brazing cemented carbide, mostly is a copper zinc alloy as the base, adding manganese, nickel, and other elements to improve the brazing seam strength. For example it with a 4% Mn, in the hard alloy brazing of YG8, YT5, YTl5 etc., joint shear strength at room temperature up to 300~320MPa; in 320 DEG C, also still have 220~240MPa, the solder is a performance of brazing cemented carbide better solder.

Comprehensive performance is better than that of copper based solder silver based solder. Silver brazing filler metals mostly used for brazing, hard alloy, but the most suitable to braze welding hard alloy of silver based brazing filler metal was added Zn, Mn, Ni and other elements of gold, silver, copper, alloy. These elements can improve the wettability of solder, brazing joint strength and improve working temperature. Silver based solder brazing temperature were lower than copper based solder, brazing to prevent crack favorable.

Composite solders in production and application is often referred to as the sandwich brazing filler metal is recently developed for a large area of hard alloy brazing new solder. The core of this solder composed of Cu Mn alloy or alloy of copper and zinc, silver based solder coated on the outside. Brazing process, the core material does not melt, just outside of silver based brazing filler metal is melted; does not melt in the high plastic copper alloy increases the brazing seam thickness. The braze metal absorbs part of the heat stress, thus greatly reduce the crack tendency of hard alloy.

Solder geometric form of the market can be seen mainly has: a straight strip, filamentous, round (rectangular) linear, strip, sheet, foil, annular, annular flat, columnar, granular, powdery, paste, adhesive tape, layered sandwich).