Brazing Filler Metals in Solder Joints

AWS Classification

Nominal Composition [%]

Brazing Range [°C]

Uses

Ag

Cu

Al

Ni

Other

BAlSi-2

-

-

92.5

-

Si, 7.5

1110 - 1150

For joining aluminum alloys and cast alloys. All these filler metals are suitable for furnace and dip brazing. BAlSi-3 and BAlSi-5 are suitable for torch brazing.

BAlSi-3

-

4

86

-

Si, 10

1160 - 1120

BAlSi-5

-

-

90

-

Si, 10

1190 - 1120

               

BAlSi-6

-

-

90

-

Si, 7.5 Mg, 2.5

1125 - 1150

Vacuum brazing filler metals. Magnesium is present as an O 2 getter.

BAlSi-8

-

-

86.5

-

Si, 12 Mg, 1.5

1080 - 1120

BAlSi-10

-

-

86.5

-

Si, 11 Mg, 2.5

1080 - 1120

BAlSi-11

-

-

88.4

-

Si, 10 Mg, 1.5 Bi, 0.1

1090 - 1120

               

BCuP-1

-

95

-

-

P, 5

1450 - 1700

For joining copper and its alloys with some limited use on silver, tungsten and molybdenum. Not for use on ferrous or nickel-based alloys. Are used for cupro-nickels, but use caution when nickel content is greater than 30 percent. Suitable for all brazing processes. Lap joints are recommended but butt joints can be used.

BCuP-3

5

89

-

-

P, 6

1300 - 1500

BCuP-5

15

80

-

-

P, 5

1300 - 1500

BCuP-7

5

88

-

-

P, 6.8

1300 - 1500

AWS Classification

Nominal Composition [%]

Brazing Range [°C]

Uses

Ag

Cu

Zn

Al

Ni

Other

BAg-1

45

15

16

-

-

Cd, 24

1145 - 1400

For joining most ferrous and nonferrous metals except aluminum and magnesium. These filler materials have good brazing properties and are suitable for preplacement in the joint or for manual feeding into the joint. All methods of heating may be used. Lap joints are used. However, butt joints can be used.

BAg-2

35

26

21

-

-

Cd, 18

1295 - 1550

BAg-4

40

30

28

-

2

-

1435 - 1650

BAg-6

50

34

16

-

-

-

1425 - 1600

BAg-8

72

28

-

-

-

-

1435 - 1650

BAg-13

54

40

5

-

1

-

1575 - 1775

BAg-18

60

30

-

-

-

Sn, 10

1325 - 1550

BAg-20

30

38

32

-

-

-

1410 - 1600

BAg-22

49

16

23

-

4.5

Mn, 7.5

1290 - 1525

BAg-24

50

20

28

-

2

-

1305 - 1550

BAg-26

25

38

33

-

2

Mn, 2

1475 - 1600

BAg-28

40

30

28

-

-

Sn, 2

1310 - 1550

AWS Classification

Nominal Composition [%]

Brazing Range [°C]

Uses

Ni

Cu

Cr

B

Si

Other

BCu-1

-

100

-

-

-

-

2000 - 2100

For joining various ferrous and nonferrous metals. They can also be used with various brazing processes. Avoid overheating the Cu-Zn alloys. Lap and butt joints are commonly used.

BCu-2

-

86.5

-

-

-

O, 13.3

2000 - 2100

RBCuZn-A

-

59

-

-

-

Zn, 41

1670 - 1750

RBCuZn-C

-

58

-

-

0.1

Zn, 40 Fe, 0.7 Mn, 0.3 Sn, 1

1670 - 1750

RBCuZn-D

10

48

-

-

0.2

Zn, 42

1720 - 1800

BCuZn-E

-

50

-

-

-

Zn, 50

1610 - 1725

BCuZn-F

-

50

-

-

Zn, 46.5

Sn, 3.5

1580 - 1700

BCuZn-G

-

70

-

-

-

Zn, 30

1750 - 1850

BCuZn-H

-

80

-

-

-

Zn, 20

1830 - 1950

                 

BAu-1

-

63

-

-

-

Au, 37

1860 - 2000

For brazing of iron, nickel, and cobalt-based metals where resistance to oxidation or corrosion is required. Low rate of interaction with base metal facilitates use on thin base metals. Used with induction, furnace, or resistance heating in a reducing atmosphere or in a vacuum and with no flux. For other applications, a borax-boric acid flux is used.

BAu-2

-

20.5

-

-

-

Au, 79.5

1635 - 1850

BAu-4

18.5

-

-

-

-

Au, 81.5

1740 - 1840

BAu-6

22

-

-

-

-

Au, 70 Pd, 8

1915 - 2050

                 

BCo-1

17

-

-

-

8

Cr, 19; W, 4; B, 0.8; C, 0.4; Co, 59

2100 - 2250

Generally used for high temperature properties and compatibility with cobalt-based metals.