Classification and Mark of Copper Base Brazing Filler
Copper brazing filler metal is a welding material consisting of a combination of copper and other alloys, typically including zinc, tin, silver and phosphorus. It is used to join two separate pieces of metal together with a gas torch or electric-arc. This technique of brazing is often used for repair or assembly of non-structural components and is valued for its ability to produce strong and reliable bonds without the need to heat the surrounding area of the joint.
The main types of copper brazing filler metal can be categorised as: low-temperature, medium-temperature and high-temperature. Low-temperature brazing filler metals contain lower levels of active ingredients, usually between 10-20%. These alloys are best suited for joining copper and copper alloys, and other materials, such as stainless steel and aluminium, which require lower temperatures than other filler metals. Examples of low-temperature copper alloys include: Cadmium-Copper-Phosphorus and Flame Brazing.
The next category of copper alloys is medium-temperature, which typically have higher levels of active ingredients, usually between 20-40%. These alloys can be used for a range of applications and materials, including copper, copper alloys and stainless steel. Examples of these processes include: Silver brazing, Copper-Silver-Phosphorus and Copper-Zinc-Phosphorus.
High-temperature copper brazing filler metals contain the highest levels of active ingredients, usually between 40-60%. These alloys are typically used for joining materials, such as steel and iron, which require temperatures higher than low- or medium-temperature processes. Examples of these alloys include: Copper-Silver-Zinc and Silver-Copper-Phosphorus alloys.
Copper brazing filler metals can also be categorised by the mark they have been assigned. These marks can range from BCuP-6 to BCuP-35 depending on the level of active ingredients and heating temperature they contain. For example, BCuP-6 is usually used for low temperature applications, such as silver brazing, while BCuP-35 is used for higher temperature processes, such as copper-silver-zinc brazing.
In summary, copper brazing filler metal can be categorised into low-, medium- and high-temperature alloys, as well as by the mark assigned to them. Each type of alloy can be used for a range of materials and applications, from copper and copper alloys to stainless steel and iron. When determining which copper brazing filler metal to use for a particular project, it is important to take into consideration its mark and the materials being joined.
