Copper-phosphorus and copper-phosphorus-silver alloys are widely used in copper and copper alloy brazing. They can also be used without flux thanks to the presence of phosphorus, with the exception of copper/brass and copper/bronze welds.
The addition of silver guarantees a greater alloy ductility, allows for a reduced melting point and increases electrical conductivity in the alloy.
These brazing alloys are not recommended for use in the presence of steels and alloys with a high nickel content. Otherwise, the joint welding will be very fragile.
SALDFLUX produces two different types of copper-phosphorus alloy. FOS® and SILVERFOS® alloys are for general use, with excellent flowability, while DULLFOS® alloys are highly recommended in the refrigeration sector or where the brazing gap is larger.
FOS - SILVERFOS - DULLFOS® | |||||||
---|---|---|---|---|---|---|---|
Name | ISO17672 | ISO3677 | Temp. Fusion °C | ||||
Ag | Cu | P | Sn | ||||
FOS 677 | - | 86 | 7 | 7 | CuP 386 | - | c.a. 650 - 700° C |
FOS 60 | - | 94 | 6 | - | CuP 179 | - | c.a. 710 - 890°C |
FOS 70 | - | 93 | 7 | - | CuP 180 | - | c.a. 710 - 820°C |
FOS 80 | - | 92 | 8 | - | CuP 182 | - | c.a. 710 - 770°C |
SILVERFOS 202 | 0,2 | 93,2 | 6,6 | - | - | B-Cu94PAg | c.a. 710 - 790°C |
SILVERFOS 204 | 0,4 | 93,6 | 6 | - | - | B-Cu94PAg | c.a. 710 - 790°C |
SILVERFOS 2 | 2 | 91,7 | 6,3 | - | CuP 279 | - | c.a. 645 - 825°C |
SILVERFOS 280 | 2 | 91 | 7 | - | CuP 280 | - | c.a. 643 - 788°C |
SILVERFOS 5 | 5 | 89 | 6 | - | CuP 281 | - | c.a. 645 - 815°C |
SILVERFOS 6 | 6 | 87 | 7 | - | CuP 283 | - | c.a. 643 - 813°C |
SILVERFOS 15 | 15 | 80 | 5 | - | CuP 284 | - | c.a. 645 - 800°C |
SILVERFOS 18 | 18 | 75 | 7 | - | CuP 285 | - | c.a. 643 - 666°C |
DULLFOS® 70 | - | 93 | 7 | - | CuP 180 | - | c.a. 710 - 925 °C |
DULLFOS® 2 | 2 | 62 | 6 | - | CuP 279 | - | c.a. 645 - 825 °C |
DULLFOS® 5 | 5 | 89 | 6 | - | CuP 281 | - | c.a. 645 - 815 °C |
DULLFOS® 15 | 15 | 85 | 5 | - | CuP 284 | - | c.a. 650 - 800 °C |
SILVERFOS 52 | 5 | 88 | 7 | CuP 282 | c.a. 645 - 771 °C |