C44300 C23000 ASTM B111 Admiralty Brass Copper Tubes
1. Introduction
This analysis focuses on two types of copper tubes, C44300 and C23000, which comply with the ASTM B111 standard. ASTM B111 is dedicated to seamless copper and copper - alloy condenser tubes and ferrule stock, ensuring high - quality standards for various industrial applications.
2. Chemical Composition
2.1 C44300 Admiralty Brass
- Copper (Cu): Ranges from 70% to 73%. Copper forms the base of this alloy, providing good electrical and thermal conductivity, as well as corrosion resistance to a certain extent.
- Zinc (Zn): The majority of the remaining composition is zinc, which is added to increase strength and improve the alloy's workability.
- Tin (Sn): Present in the range of 0.9% - 1.2%. Tin enhances the alloy's corrosion resistance, especially in marine environments.
- Trace Elements: Iron (Fe) is limited to ≤0.06% and lead (Pb) to ≤0.07%. These trace elements are controlled to maintain the alloy's desired properties.
2.2 C23000 Brass
- Copper (Cu): Comprises 84% - 86% of the alloy. High copper content gives C23000 good electrical conductivity and a characteristic red - golden color.
- Zinc (Zn): The remaining part is mainly zinc, which, like in C44300, contributes to strengthening the alloy and enhancing its formability.
- Trace Elements: Lead (Pb) content is typically set at 0.05%, and iron (Fe) at 0.05%. These small amounts of impurities are carefully controlled to ensure optimal performance in terms of machinability and mechanical properties.
3. Mechanical Properties
3.1 C44300 Admiralty Brass
- Tensile Strength: The minimum tensile strength is 310 MPa. This relatively high value makes C44300 suitable for applications where the tube needs to withstand significant pulling forces, such as in heat exchanger tubes in industrial settings.
- Yield Strength: With a minimum of 105 MPa, C44300 can resist plastic deformation to a certain extent under applied stress, ensuring the integrity of the tube during normal operation.
- Elongation: It has good ductility, with an elongation at break of around 30% - 45%. This property allows the tube to be easily formed into various shapes during manufacturing processes like bending and flanging.
3.2 C23000 Brass
- Tensile Strength: Generally lower than C44300, with a range of 276 - 345 MPa. This makes it less suitable for applications that require extremely high - strength materials but still adequate for many general - purpose uses.
- Yield Strength: Lower as well, typically in the range of 103 - 172 MPa. Despite the lower yield strength, C23000 can still maintain its shape under normal stress conditions in common applications.
- Elongation: Exhibits high ductility, often with an elongation at break over 50%. This excellent ductility makes C23000 highly formable, which is beneficial for manufacturing complex - shaped plumbing fittings and decorative items.
4. Corrosion Resistance
4.1 C44300 Admiralty Brass
- Marine and Industrial Corrosion Resistance: C44300 is renowned for its outstanding resistance to seawater corrosion. The combined effect of tin in its composition provides a protective barrier against the harsh marine environment. It is highly resistant to dezincification, which is a major concern in copper - zinc alloys when exposed to seawater or other corrosive waters. This makes it an ideal choice for condenser, evaporator, and heat exchanger tubes in marine applications, as well as in industrial settings where there is exposure to sulfur - compound - containing and contaminated water, such as in oil refineries.
4.2 C23000Brass
- General Corrosion Resistance: C23000 has good general corrosion resistance. It can withstand the normal corrosion encountered in fresh - water plumbing systems and some mild - corrosive environments. However, compared to C44300, its resistance to seawater and highly corrosive industrial environments is relatively lower. This limits its use in applications where exposure to harsh corrosive media is expected.
5. Machinability
5.1 C44300 Admiralty Brass
- Fair to Good Machinability: C44300 has fair to good machinability. The presence of alloying elements like tin affects the cutting process. During machining, proper tool selection is crucial. Carbide - tipped tools are often preferred due to the alloy's hardness. Additionally, appropriate cutting parameters, such as cutting speed, feed rate, and depth of cut, need to be carefully adjusted to achieve good surface finish and efficient machining. For example, a relatively lower cutting speed may be required compared to some pure copper or less - alloyed materials to prevent tool wear.
5.2 C23000 Brass
- Excellent Machinability: C23000 offers excellent machinability, especially when lead is present in its composition. The addition of a small amount of lead acts as a lubricant during machining, making it easy to cut, drill, and thread. This property is highly beneficial for manufacturing complex - shaped parts, such as plumbing fittings with intricate designs. High - speed steel tools can be used effectively for machining C23000, and relatively high cutting speeds and feed rates can be employed, resulting in high - productivity manufacturing processes.
6. Applications
6.1 C44300 Admiralty Brass
- Marine Applications: Widely used in marine heat exchangers, condensers, and evaporators. In ships, C44300 tubes are used to transfer heat between seawater and other fluids, taking advantage of its excellent seawater corrosion resistance.
- Industrial Applications: Used in power generation plants for cooling water systems. It is also suitable for heat - exchanger equipment in various industries, such as chemical plants, where it can withstand the corrosive effects of process fluids.
6.2 C23000 Brass
- Plumbing Applications: Commonly used in plumbing systems, including water pipes, fittings, and valves. Its good corrosion resistance in fresh - water environments, combined with excellent formability and machinability, makes it a popular choice for these applications.
- Decorative Applications: Due to its attractive red - golden color, C23000 is often used in decorative items such as doorknobs,and other architectural and interior design elements.
Short Description:
This specification establishes the reguirements for seamless tube and ferrule stock of copper and various copper alloys of a specified range of diameters, for use in surface condensers, evaporators and heat exchangers.
The specified coppers and copper alloys are UNS No. C10100,C10200,C10300,C10800,C12000,C12200,C14200,C19200,C23000,C28000,C44300,C44400,
C44500,C60800,C61300,C61400,C68700,C70400,C70600,C70620,C71000,C71500, C71520,C71640 and C72200. The product shall be produced by processes such as casting, extrusion, drawing, annealing, straightening, trimming, and other processes which may produce a seamless tube in the specified condition. The coppers and copper alloys shall be specifically furnished in any one of the following tempers.: annealed, light-drawn, hard-drawn, or hard drawn and end annealed. Tubes for ferrule stock shall be annealed sufficiently to be fully crystallized.
Some tubes are suggested to be subjected to a stress-relieving thermal treatment subsequent to
straightening. The products shall be subjected to expansion, flattening, and residual stress tests
The tensile and expansion requirements for the products are specified in accordance with the
temper desianation. The products shall also be subjected to mercurous nitrate, ammonia vapor.
Eddy-current, hydrostatic, and pneumatic tests.
ASTM Standards:
- B153 Test Method for Expansion (Pin Test) of Copper and Copper-Alloy Pipe and Tubing.
- B154 Test Method for Mercurous Nitrate Test for Copper and Copper Alloys.
- B170 Specification for Oxygen-Free Electrolytic Copper Refinery Shapes.
- B224 Classification of Coppers.
- B846 Terminology for Copper and Copper Alloys.
- B858 Test Method for Ammonia Vapor Test for Determining Susceptibility to Stress Corrosion Cracking in Copper Alloys.
- E8 Test Methods for Tension Testing of Metallic Materials E 8M Test Methods for Tension Testing of Metallic Materials [Metric].
- E29 Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications.
- E53 Test Methods for Determination of Copper in Unalloyed Coppers by Gravimetry.
- E54 Test Methods for Chemical Analysis of Special Brasses and Bronzes.
- E62 Test Methods for Chemical Analysis of Copper and Copper Alloys (Photometric Methods.
- E75 Test Methods for Chemical Analysis of Copper-Nickel and Copper-Nickel-Zinc Alloys.
- E76 Test Methods for Chemical Analysis of Nickel-Copper Alloys.
- E112 Test Methods for Determining Average Grain Size E 243 Practice for Electromagnetic (Eddy Current) Examination of Copper and Copper-Alloy Tubes.
- E255 Practice for Sampling Copper and Copper Alloys for the Determination of Chemical Composition.
- E478 Test Methods for Chemical Analysis of Copper Alloys.
- E527 Practice for Numbering Metals and Alloys (UNS).
Chemical Composition:
| Designation |
Chemical Composition % |
| Cu |
Sn |
Al |
As |
Ni |
Fe |
Mn |
Pb max. |
Zn |
| C44300 |
70.0-73.0 |
0.9-1.2 |
- |
0.02-0.06 |
- |
0.06 max |
- |
0.07 |
Rem |
| C68700 |
76.0-79.0 |
- |
1.8-2.5 |
0.02-0.06 |
- |
0.06 max |
- |
0.07 |
Rem |
| C70400 |
Rem |
- |
- |
- |
4.8-6.2 |
1.3-1.7 |
0.3-0.8 |
0.05 |
1.0max |
| C70600 |
Rem |
- |
- |
- |
9.0-11.0 |
1.0-1.8 |
1.0max |
0.05 |
1.0max |
| C71500 |
Rem |
- |
- |
- |
29.0-33.0 |
0.4-1.0 |
1.0max |
0.05 |
1.0max |
| C71640 |
Rem |
- |
- |
- |
29.0-32.0 |
1.7-2.3 |
1.5-2.5 |
0.05 |
1.0max |
The world standard Grade equivalent to ASTM B111
| Material Designation |
Corresponding Material Symbol |
| GB/T8890 |
ASTM B111 |
BS2871 |
JIS H3300 |
DIN1785 |
| Copper-Nickel |
BFe10-1-1 |
C70600 |
CN102 |
C7060 |
CuNi10Fe1Mn |
| BFe30-1-1 |
C71500 |
CN107 |
C7150 |
CuNi30Mn1Fe |
| (BFe30-2-2) |
C71640 |
CN108 |
C7164 |
CuNi30Fe2Mn2 |
| (BFe5-1.5-0.5) |
C70400 |
- |
- |
- |
| B7 |
- |
- |
- |
- |
| Aluminums Brass |
HAL77-2 |
C68700 |
CZ110 |
C6870 |
CuZn20Al2 |
| Admiralty Brass |
HSn70-1 |
C44300 |
CZ111 |
C4430 |
CuZn28Sn1 |
| Boric Brass |
Hsn70-18 |
- |
- |
- |
- |
| HSn70-1 AB |
- |
- |
- |
- |
| Arsenical Brass |
H68A |
- |
CZ126 |
- |
- |
| Brass Tube |
H65/H63 |
C28000/C27200 |
CZ108 |
C2800/C2700 |
CuZn36/CuZn37 |
Tensile Requirements
| Copper or Copper Alloy UNS NO. |
Temper Designation |
Tensile Strength |
Yield Strength |
| Standard |
Former |
min ksi |
min ksi |
| C44300 |
O61 |
annealed |
45 |
15 |
| C68700 |
O61 |
annealed |
50 |
18 |
| C70400 |
H55 |
light-drawn |
38 |
30 |
| C70600 |
H55 |
light-drawn |
45 |
15 |
| C71500 |
O61 |
annealed |
52 |
18 |
| C71640 |
O61 |
annealed |
63 |
25 |
Expansion Test
- Tube specimens selected for test shall withstand the expansion shown in standard when expanded in accordance with Test Method B 153. The expanded tube shall show no cracking or rupture visible to the unaided eye.
- Hard-drawn tubes not end annealed are not subject to this test. When tubes are specified end annealed, this test is required and shall be performed on the annealed ends of the sampled tubes.
- Tubes for ferrule stock are not subject to the expansion test.
Flattening Test
- Test Method-Each test specimen shall be flattened in a press at three (3) places along the length, each new place to be rotated on its axis approximately one third turn from the last flattened area. Each flattened area shall be at least 2 in. in length. A flattened test-specimen shall allow a micrometer caliper set at three (3) times the wall thickness to pass freely over the flattened area. The flattened areas of the test specimen shall be inspected for surface defects.
- During inspection, the flattened areas of the test- specimen shall be free of defects, but blemishes of a nature that do not interfere with the intended application are acceptable.
- Tubes for ferrule stock are not subject to flattening test.
Residual Stress Test
- A residual stress test is required to be performed only for Copper Alloy UNS Nos. C23000, C28000, C44300, C44400, C44500, C60800, C61300, C61400, and C68700.
- Unless otherwise specified, the producer shall have the option of testing the product to either the mercurous nitrate test, Test Method B 154, or the ammonia vapor test, Test Method B 858, as prescribed below.
Nondestructive Testing
Eddy-Current Test-Each tube shall be passed through an eddy-current testing unit adjusted to provide information on the suitability of the tube for the intended application. Testing shall follow the procedures of Practice E 243.
Hydrostatic Test
Each tube shall stand, without showing evidence of leakage, an internal hydrostatic pressure sufficient to subject the material to a fiber stress of 7000 psi [48 MPa] as determined by the following equation for thin hollow cylinders under tension. The tube need not be tested at a hydrostatic pressure of over 1000 psi [7.0 MPa] unless so specified.
Detailed Photos
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