Composite solder is a kind of brazing material which is made of two or three layers of plate, strip or foil by compounding a certain thickness of solder layer on one or both sides of the base material in different ways. Composite solder is not only a kind of metal composite material, but also a kind of functional material with special use.
In the process of using composite solder, the soldered materials are brazed together by melting the solder layer. This kind of composite solder is suitable for brazing large area and joint-intensive mechanical parts. For example, automobile radiators (condensers, evaporators, oil coolers, intercoolers, heaters and water tanks), as well as oxygen generator radiators and diesel engine coolers, and other mechanical radiators and coolers. For stainless steel, ferronickel alloy, copper or aluminium radiator and cooler, brazing these parts with corresponding composite brazing filler metal can not only weld large area and multi-joint materials, but also reinforce parts and simplify the assembly process. It has the advantages of high efficiency, good quality and low cost. The facts show that composite solder is an indispensable heat exchange material for manufacturing radiators in mechanical industry.
There are several kinds of composite solders developed and produced by Henan Chalco.
1) Composition of three-layer aluminium alloy composite brazing filler metal: the middle layer is aluminium-manganese alloy, and the two sides are aluminium-silicon alloy. They are used for brazing automotive parts such as aluminium automotive radiators.
2) Composite brazing filler metal coated with stainless steel. The intermediate layer of the composite brazing filler metal is 18-8 stainless steel with silver-lithium alloy on both sides. It can braze stainless steel and Iron-Nickel Base Superalloys without flux at 850-940 C under gas shielding or low vacuum conditions.
3) When brazing the composite brazing material BTB plate of titanium heat exchanger, a three-layer structure composite plate is composed of titanium plate in the middle layer and low temperature brazing material in the upper and lower layers. When BTB board has outstanding characteristics, it can easily weld multi-layer titanium honeycomb corrugated plate into a whole by vacuum brazing.
4) Composite brazing filler metal for cemented carbide and steel workpiece. The composite brazing filler metal consists of three layers, two outer layers are a silver brazing alloy, and the core layer is a copper-based alloy. The composite brazing filler metal is mainly used for brazing cemented carbide steel workpieces. The joint has good shear strength and impact strength.
