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Composition by weight %
Family
Solidus/liquidus
point (°C)
Toxic
Comments
Cu
Zn
Ag
Au
Pd
Pt
Ti
Cr
Mo
W
Mn
Fe
Co
Ni
Cd
Sn
Al
B
Si
P
other
Cu
85.3
Sn
7
P
6.2
Ni
1.5
Cu–Sn
612/682
[29]
–
Fos-Flo 671. Low-cost. Useful for joining copper to copper or copper alloys where
strong impacts and vibrations are not encountered. Requires good fitup. Self-
fluxing on copper. Silver-free. Extremely fluid above flow point, for tight-fitting joints.
Gap 0.025–0.075 mm.
85.3
1.5
7
6.2
Cu
58.5
Zn
41.3
Si
0.2
Cu–Zn
875/895
[1][11]
–
CU 301. Brass. Brasses are often used on mild steel assemblies. For use on brass,
bronze, and low carbon steel. Used in plumbing.
58.5
41.3
0.2
Cu
58.5
Zn
41.1
Sn
0.2
Si
0.2
Cu–Zn
875/895
[1][11]
–
CU 302. Brass. For carbon steel and galvanized steel. Used in plumbing.
58.5
41.1
0.2
0.2
Cu
60
Zn
39.55
Si
0.3
Mn
0.15
Cu–Zn
870/900
[1]
–
CU 303. Brass.
60
39.55
0.15
0.3
Cu
60
Zn
39.8
Ni
10
Si
0.2
Cu–Zn
875/890
[30]
–
BrazeTec 60/40. For brazing zinc-coated tubes. Similar to CU 303.
60
39.8
0.2
Cu
60
Zn
29.35
Sn
0.35
Si
0.3
Cu–Zn
870/900
[1]
–
CU 304. Brass.
60
29.35
0.35
0.3
Cu
60
Zn
40
Cu–Zn
865/887
[26]
–
RBCuZn-C, CDA 681. Brass. Fluid. For alloys of iron, copper, and nickel.
60
40
Cu
46
Zn
45.4
Sn
0.5
Si
0.1
Ni
8
Cu–Zn
890/920
[1][11]
–
CU 305. Brass. For use on carbon and galvanized steel, slightly higher tensile
strength than CU 302. Used in plumbing.
46
45.4
8
0.5
0.1
Cu
48
Zn
41.8
Ni
10
Si
0.2
Cu–Zn
890/920
[30]
–
BrazeTec 48/10. For brazing steel tube frames.
48
41.8
10
0.2
Cu
56
Zn
38.25
Sn
1.5
Si
0.5
Mn
0.2
Ni
0.2
Cu–Zn
870/890
[1][11]
–
CU 306. Brass. For use on cast and malleable iron. Used in plumbing.
56
38.25
0.2
0.2
1.5
0.5
Cu
54.85
Zn
25
Mn
12
Ni
8
Si
0.15
Cu–Zn
855/915
[31]
–
Hi-Temp 080. Economical. High-strength. For attaching carbides to alloy steels.
Light yellow joint.
54.85
25
12
8
0.15
Cu
52.5
Mn
38
Ni
9.5
Cu–Mn
855/915
[31]
879/927
[32]
–
AMS 4764, Hi-Temp 095, Nicuman 38. High-strength. For carbides, steels,
stainless steels, cast iron, and nickel refractory alloys. Ideal for combined
brazing/heat treatment. Good for materials where copper-brazing would require too
high temperature or where boron alloys would be detrimental. Relatively free-
flowing; melting point may rise when more nickel is dissolved from the base metal.
Fluxless brazing requires vacuum, argon or dry hydrogen atmosphere. Reddish
gray color.
52.5
38
9.5
Cu
67.5
Mn
23.5
Ni
9
Cu–Mn
925/955
–
Nicuman 23.
67.5
23.5
9
Cu
55
Zn
35
Ni
6
Mn
4
Cu–Zn
880/920
[31]
866/885
[33]
–
Hi-Temp 548, Silvaloy X55. Modified nickel-silver. Moderate-strength, tough.
Excellent plasticity in molten state. Gap-filling. Excellent strength and ductility
during cooling, which is an advantage over silver brazes when joining materials
with dissimilar thermal expansion. For carbides, stainless steels, tool steels, and
nickel alloys. Used for joining carbide tool tips to steel holders. Light yellow color.
May contain 0.2% silicon for better flow. For induction, torch and furnace brazing.
55
35
4
6
Cu
87
Mn
10
Co
2
Cu–Mn
960/1030
[31]
–
Hi-Temp 870. High-temperature strength. Free-flowing. For carbides, stainless
steels, tool steels, and nickel alloys. Excellent wetting of carbides, stainless steel
and copper. Good gap-filling at lower brazing temperatures. Fluxless brazing
possible in vacuum or suitable atmosphere. Brazing often done together with heat
treatment.
87
10
2
Cu
87.75
Ge
12
Ni
0.25
Cu
880/975
[34]
–
Gemco. Used for special purposes, e.g. brazing CFC (carbon fibre composites),
pure copper, copper-zirconium alloys and molybdenum.
[35]
As the braze does not
contain active elements, the carbon-based material may have to be surface-treated
for sufficient wetting, e.g. by a solid-state reaction with chromium.
[36]
87.5
0.25
Ge
12
Ag
38
Cu
32
Zn
28
Sn
2
Ag–
Cu–Zn
649/721
[10]
650/720
[37]
660/720
[38]
–
BAg-34, AMS 4761, Braze 380, Silvaloy A38T, Silver Braze 38. Free-flowing, for
ferrous alloys, nickel, copper and their alloys, and combinations. Tin content
improves wetting of tungsten carbide, stainless steel, and other difficult metals.
Absence of lead and cadmium allows use of long heating cycles. Cheaper
alternative of BAg-28 with similar properties. Suitable for fluxless controlled
atmosphere brazing. Mostly used in furnace brazing. Best for narrow gaps. General
purpose alloy for air conditioning applications for joining steels, copper, and copper
and nickel alloys. Gap 0.075–0.2 mm. Pale yellow color. Maximum service
temperature 204 °C (intermittently 316 °C).
32
28
38
2
Ag
40
Cu
30
Zn
30
Ag–
Cu–Zn
674/727
[10]
675/725
[37]
–
Braze 401, AMS 4762. Low-temperature, fairly free flowing. Narrow melting range.
For ferrous and non-ferrous metals. For copper alloys, brass, nickel silver, bronze,
mild steel, stainless steel, nickel, and Monel. Cadmium-free substitute of BAg-2a.
Moderate liquation, but can be exploited for bridging larger gaps. Pale yellow color.
30
30
40
Ag
45
Cu
30
Zn
25
Ag–
Cu–Zn
663/743
[10][39]
665/745
[37]
675/735
[40]
–
BAg-5, Braze 450, Silvaloy A45, Matti-sil 45, Silver Braze 45. Low-temperature.
For ferrous, non-ferrous, and dissimilar metals. For band instruments, brass lamps,
ship piping, aircraft engine oil coolers. Can be used in food industry. Allows larger
joint clearances. Melting range sufficient to braze joints with gaps commonly
encountered in commercial tubing and fittings. Yellow white color. Maximum service
temperature 204 °C (intermittently 316 °C). Gap 0.075–0.2 mm.
30
25
45
Ag
45.75
Cu
18.3
Zn
25.62
Ni
1.93
Ag–
Cu–Zn
–
18.3
25.62
45.75
1.93
Ag
50
Cu
20
Zn
28
Ni
2
Ag–
Cu–Zn
660/707
[10]
660/705
[41]
–
BAg-24, AMS 4788, Braze 505, Silvaloy A50N, Argo-braze 502, Silver Braze
50Ni2. For most metals, incl. stainless steel and carbides. Highly recommended.
Recommended for 300-series stainless steel. Good for food-handling applications
with close joint tolerances. Gap 0.1–0.25 mm. Alloy specifically designed for
brazing tungsten carbide tips to steel tools and wear parts. Readily wets nickel and
iron alloys. Nickel offsets embrittlement by aluminium diffusion when brazing
aluminium bronzes. Retards interface corrosion where base metals can cope. Zinc-
free alloys suggested where there is a risk of dezincification, e.g. exposure to salt
water at high temperatures. Very fluid, quickly fills long narrow joints. Tends to
liquate. Yellow-white color. Cadmium-free replacement for BAg-3.
20
28
50
2