Copper Alloys Naval Brass C46400

 Product Data Sheet – Copper Alloys

Naval Brass, Uninhibited  UNS-C46400

What is Naval Brass?

Naval Brass is a 60:40 copper zinc alloy to which about 1% of tin has been added to improve the corrosion resistance, particularly to dezincification. The alloy is a two phase alpha-beta brass, or duplex brasses, hence has reasonably high strength with lower ductility than the single-phase 70:30 or alpha brass. It is used for structural applications and for forgings, especially where contact with sea water is likely to induce corrosion. The mechanical properties are almost indistinguishable from those of 60:40 brass C28000, although the tin addition tends to give slightly higher strength.

C46400 can be readily hot worked, and can also be cold worked, but not as easily as the single phase alpha brasses.

Typical Applications

C46400 naval brass alloys exhibit unique properties that lend itself suitable for the following applications:

  • marine hardware, propeller shafts, heat exchanger tube, condenser plates, valve stems, marine construction, marine atmosphere applications, baffle plates, condenser tubes, pressure vessels, hardware applications.

Other grades

Naval brass can be sourced is grades/alloy composition other than C46400, these include C46200, C48200 and C48500, with these alloys more commonly found in bar and rod products.

Chemical Composition

(% maximum, unless shown as range or minimum)

CopperIronLeadTinZinc
Min/Max
59.0-62.0
0.10
0.20
0.50-1.00
Remainder
Nominal
60.0
0.7
39.2

Copper + Sum of Named Elements, 99.6% minimum

Applicable Specifications

ProductSpecifications
AMSASMEASTMFederalMilitarySAE
Bar
4611, 4612
B21
QQ-B-639
J461, J463
Bar, Forging
B124
Bolts
F468
Forgings, Die
B283
Nuts
F467
Plate
QQ-B-639
Plate, Clad
B432
Plate, Condenser Tube
SB171
B171
Rod
4611, 4612
B21
J461, 463
Rod, Forging
B124
Screws
F468
Shapes
B21
Shapes, Forging
B124
Sheet
QQ-B-639
Strip
QQ-B-639
J461, J463
Studs
F468
Wire, Metallizing
MIL-W-6712

Room Temperature, 20°C

Temper
Section Size
Cold Work
Temperature
Tensile Strength
Yield Strength(0.5% ext under load)ElongationRockwell Hardness
Vickers Hardness
Shear Strength
mm
%
°C
MPa
MPa
%BCF30T0.5MPa
Flat Products
H01
1
0
20
483
400
17
75
68
138
296
M20
25.4
0
20
379
172
50
55
55
99
276
O50
1
0
20
427
207
40
60
57
107
283
O50
6.35
0
20
414
193
45
58
56
104
283
O60
6.35
0
20
400
172
49
56
55
100
276
Rod
H01
6.35
10
20
483
331
25
80
150
296
H01
25.4
8
20
476
317
27
78
146
296
H01
51
8
20
462
276
35
75
138
296
H02
6.35
20
20
552
393
20
85
164
310
H02
25.4
20
20
517
365
20
82
156
303
O50
6.35
0
20
434
207
40
60
107
290
O50
25.4
0
20
434
207
40
60
107
290
O50
51
0
20
427
193
43
60
170
290
O60
6.35
0
20
400
186
45
56
100
276
O60
25.4
0
20
393
172
47
55
99
276
O60
51
0
20
386
172
47
55
99
276
Tube
H80
0.0
35
20
607
455
18
95
200

Mechanical Properties

Common Fabrication Processes

Blanking, Drawing, Forming and Bending, Heading and Upsetting, Hot Forging and Pressing, Hot Heading and Upsetting, Shearing

Fabrication Properties

Joining TechniqueSuitability
Soldering
Excellent
Brazing
Excellent
Oxy Acetylene Welding
Good
Gas Shielded Arc Welding
Fair
Coated Metal Arc Welding
Not Recommended
Spot Welding
Good
Seam Welding
Fair
Butt Welding
Good
Fabrication TechniqueSuitability
Capacity for Being Cold Worked
Fair
Capacity for Being Hot Worked
Excellent
Forgeability Rating
90% *
Machinability Rating
30% **

* of C37700 (forging brass)

** of C36000 (free cutting brass)

Typical Uses

IndustryUses
Builders Hardware
Lock Pins
Electrical
Precision Shipboard Equipment
Fasteners
Nuts, Rivets, Bolts
Industrial
Hub Cones, Balls, Aircraft Turn Buckle Barrels, Valve Stems, Condenser Plates, Dies, Golf Ball Production, Pressure Vessels, Bearings, Bushings, Heat Exchanger Tube, Welding Rod, Structural Uses
Marine
Decorative Fittings, Propeller Shafts, Turn Buckles, Shafting, Marine Hardware, Propeller Shafts
Ordinance
Missile Components
Other
Baffle Plates & Flanges
Plumbing
Fittings

Phase Diagram & Mechanical Properties

Copper Alloys Naval Brass C46400 - Properties

Corrosion Resistance

The addition of tin gives this alloy an inherent resistance to dezincification, further inhibiting the impingement by seawater at higher than normal temperatures. C46400 naval brass is also noted for its resistance to wear, fatigue, galling, and stress corrosion cracking.

C46400 has good corrosion resistance to weathering and good resistance to many waters. It was developed to resist the dezincification in sea water which may be encountered with plain 60:40 brass, C28000.

Low-copper alloys, such as naval brass appear to form thin, adherent surface films of corrosion products which are moderately protective.

C46400 should not be used in contact with ammonia, ammonia compounds or amines, as it may suffer stress corrosion cracking. It may also suffer stress corrosion cracking in atmospheric exposures.

Please consult Austral Wright Metals for advice on your specific application.

Marine Atmospheric Exposure

Copper alloys are often specified for marine atmospheric exposures because of the attractive and protective patina they form during the exposure by mild surface corrosion. The corrosion rate slows during the exposure.

Naval brass generally darkens to a deep chocolate brown colour. It is not expected to form the green patina often seen on alloys richer in copper, especially on material mounted vertically.

Differences between the corrosion rates of various alloys do exist, but they are usually less than the differences caused by the environment. Copper alloys can be classed into a group that corrodes at a moderate rate (high copper alloys, silicon bronze, tin bronze) and a group that corrodes at a slower rate (brass, aluminium bronze, nickel silver, copper nickel).

The average metal thickness loss, d, of the former group approximates to d = 0.1 t2/3, and of the latter group to d = 0.1 t1/3, where t is the exposure time.

The surface can be artificially bronzed to produce by the patina, please contact Austral Wright Metals for details. Both artificial and naturally patinated surfaces will continue to darken unless washed hot soapy water, rinsed, dried and treated with lemon oil, boiled linseed oil or castor oil. The surface will take on a mild lustre.

This sequence of washing and oiling should be repeated at about yearly intervals to maintain the metal in good condition.

Copper Alloys Naval Brass C46400 - thickness lossCopper Alloys Naval Brass C46400 - thickness loss
Moderate corrosion rate group (high copper alloys, silicon bronze, tin bronze)Low corrosion rate group (brass, aluminium brass, nickel silver, copper nickel)

The surface can be artificially bronzed to produce by the patina, please contact Austral Wright Metals for details. Both artificial and naturally patinated surfaces will continue to darken unless washed hot soapy water, rinsed, dried and treated with lemon oil, boiled linseed oil or castor oil. The surface will take on a mild lustre.

This sequence of washing and oiling should be repeated at about yearly intervals to maintain the metal in good condition.

Physical Properties

Property
Metric Units
Imperial Units
Melting Point (Liquidus)
899°C
1650°F
Melting Point (Solidus)
888°C
1630°F
Density
8.41 gm/cm³ @ 20°C
0.304 lb/in³ @ 68°F
Specific Gravity
8.41
8.41
Coefficient of Thermal Expansion
21.2 x 10 -6 / °C (20-300°C)
11.8 x 10 -6 / °F (68-572°F)
Themal Conductivity
120 W/m. °K @ 20°C
67 BTU/ft2/ft/hr/°F @ 68°F
Thermal Capacity (Specific Heat)
377.1 J/kg. °K @ 293°K
0.09 BTU/lb/°F @ 68°F
Electrical Conductivity
0.152 MegaSiemens/cm@ 20°C
26 % IACS @ 68°F
Electrical Resistivity
6.63 microhm.cm @ 20°C
39.9 ohms -cmil/ft@ 68°F
Modulus of Elasticity (tension)
103,400 MPa
15,000 ksi
Modulus of Rigidity (torsion)
38,610 MPa
5,600 ksi

Tempers Most Commonly Used

Flat Products
Bar, Drawn
H01, H02, O50, O60
Bar, Rolled
H01, O50, O60
Plate
H02, M20, O60
Strip, Rolled
H01, O50
Other Products
Rod
H01, H02, M30, O50, O60
Shapes
H01, M30
Tube
H58, H80

 

The technical advice and recommendations made in this Product Data Sheet should not be relied or acted upon without conducting your own further investigations, including corrosion exposure tests where needed. Please consult current editions of standards for design properties. Austral Wright Metals assumes no liability in connection with the information in this Product Data Sheet. Austral Wright Metals supplies a comprehensive range of stainless steels, copper alloys, nickel alloys and other high performance metals for challenging service conditions. Our engineers and metallurgists will be pleased to provide further data and applications advice.

 

BACK