Aluminum Bronzes

Overview

Aluminum bronzes are used for their combination of high strength, excellent corrosion and wear resistance. Aluminum bronze alloys typically contain 9-12% aluminum and up to 6% iron and nickel. Alloys in these composition limits are hardened by a combination of solid solution strengthening, cold work, and precipitation of an iron rich phase. High aluminum alloys are quenched and tempered. Aluminum bronzes are used in marine hardware, shafts and pump and valve components for handling seawater, sour mine waters, nonoxidizing acids, and industrial process fluids. They are also used in applications such as heavy duty sleeve bearings, and machine tool ways. They are designated by UNS C60800 through C64210. Aluminum bronze castings have exceptional corrosion resistance, high strength, toughness and wear resistance and good casting and welding characteristics. Aluminum bronze castings are designated as UNS C95200 to C95900.

The microstructure of the aluminum bronzes with less than 11% aluminum consist of alpha solid solution and the iron and nickel rich kappa phase. The kappa phase absorbs aluminum from the alpha solid solution preventing the formation of the beta phase unless the aluminum content is above 11%. The kappa phase increases the mechanical strength of the aluminum bronzes, with no decrease in ductility. The decrease in ductility of the aluminum bronzes occurs when the beta phase forms. The beta phase is harder and more brittle than the alpha phase. Beta is formed if the material is quenched or fast cooled, which then transforms into a hard, acicular martensite structure. Tempering the martensite results in a structure of alpha with kappa precipitates. The tempered structure is very desirable, it has high strength and hardness. The slow cooled, as cast structures consist of alpha and kappa phases. Kappa is present in the lamellar form and finely divided in all the alpha areas. The addition of iron and nickel also suppress the formation of the gamma double prime phase which has deleterious effects on the properties of aluminum copper alloys.

NOTE: The file size of the Larger and Largest View of the Micrographs are substantially larger than the thumbnail shown. The Larger View images range in size from 11K to 120K depending on the image. The Largest View images range in size from 125K to almost 500K.

Microstructure
Nominal Composition:
Cu 90.83, Al 6.5, Fe 2.4, Sn 0.27

Larger View of Micrograph
Largest View of Micrograph

Alloy Family: Aluminum bronzes
Product Form: Plate
Processing: Hot rolled
Etchant:
Scale Line Length: ~ 125Microns
Alloy: C61300
Temper:
Material: Aluminum bronze, 6-7.5 Al
Source: University of Florida


Microstructure
Nominal Composition:
Cu 90.83, Al 6.5, Fe 2.4, Sn 0.27

Larger View of Micrograph
Largest View of Micrograph

Alloy Family: Aluminum bronzes
Product Form: Rod
Processing: Extruded and cold drawn
Etchant:
Scale Line Length: ~ 125Microns
Alloy: C61300
Temper:
Material: Aluminum bronze, 6-7.5 Al
Source: University of Florida


Microstructure
Nominal Composition:
Cu 87.1, Al 9.3, Fe 3.6

Larger View of Micrograph
Largest View of Micrograph

Alloy Family: Aluminum bronzes
Product Form: Rod
Processing: Extruded and cold drawn 10%
Etchant:
Scale Line Length: ~ 25Microns
Alloy: C62400
Temper:
Material: Aluminum bronze, 10-11.5 Al
Source: University of Florida


Microstructure
Nominal Composition:
Cu 83.8, Al 12.0, Fe 4.2

Larger View of Micrograph
Largest View of Micrograph

Alloy Family: Aluminum bronzes
Product Form: Rod
Processing: Extruded
Etchant:
Scale Line Length: ~ 50Microns
Alloy: C62500
Temper:
Material: Aluminum bronze, 12.5-13.5 Al
Source: University of Florida


Microstructure
Nominal Composition:
Cu 82.5, Al 9.7, Ni 4.9, Fe 2.9

Larger View of Micrograph
Largest View of Micrograph

Alloy Family: Aluminum bronzes
Product Form:
Processing: As quenched from 857C
Etchant:
Scale Line Length: ~ 25Microns
Alloy: C63000
Temper:
Material: Nickel-aluminum bronze, 9.0-11.0 Al, 4.0-5.5 Ni
Source: University of Florida


Microstructure
Nominal Composition:
Cu 82.5, Al 9.7, Ni 4.9, Fe 2.9

Larger View of Micrograph
Largest View of Micrograph

Alloy Family: Aluminum bronzes
Product Form: Rod
Processing: Extruded and cold drawn
Etchant:
Scale Line Length: ~ 125Microns
Alloy: C63000
Temper:
Material: Nickel-aluminum bronze, 9.0-11.0 Al, 4.0-5.5 Ni
Source: University of Florida


Microstructure
Nominal Composition:
Cu 80.4, Al 8.9, Ni 5.0, Fe 4.7, Mn 1.0

Larger View of Micrograph
Largest View of Micrograph

Alloy Family: Aluminum bronzes
Product Form:
Processing: Extruded
Etchant:
Scale Line Length: ~ 125Microns
Alloy: C63200
Temper:
Material: Nickel-aluminum bronze, 8.7-9.5 Al , 4.0-4.8 Ni
Source: University of Florida


Microstructure
Nominal Composition:
Cu 80.4, Al 8.9, Ni 5.0, Fe 4.7, Mn 1.0

Larger View of Micrograph
Largest View of Micrograph

Alloy Family: Aluminum bronzes
Product Form:
Processing: Quenched from 927C and tempered at 705C
Etchant:
Scale Line Length: ~ 500Microns
Alloy: C63200
Temper:
Material: Nickel-aluminum bronze, 8.7-9.5 Al , 4.0-4.8 Ni
Source: University of Florida


Microstructure
Nominal Composition:
Cu 85.8, Al 10.2, Fe 4.0

Larger View of Micrograph
Largest View of Micrograph

Alloy Family: Aluminum bronzes
Product Form: Cast
Processing: Cast, annealed at 621C and water quenched
Etchant:
Scale Line Length: ~ 500Microns
Alloy: C95400
Temper:
Material: Aluminum bronze, 10-11.5 Al
Source: University of Florida

Microstructure
Nominal Composition:
Cu 85.8, Al 10.2, Fe 4.0

Larger View of Micrograph
Largest View of Micrograph

Alloy Family: Aluminum bronzes
Product Form: Cast
Processing: Annealed and furnace cooled
Etchant:
Scale Line Length: ~ 50Microns
Alloy: C95400
Temper:
Material: Aluminum bronze, 10-11.5 Al
Source: University of Florida

Microstructure
Nominal Composition:
Cu 85.8, Al 10.2, Fe 4.0

Larger View of Micrograph
Largest View of Micrograph

Alloy Family: Aluminum bronzes
Product Form: Cast
Processing: Annealed at 621C and water quenched
Etchant:
Scale Line Length: ~ 25Microns
Alloy: C95400
Temper:
Material: Aluminum bronze, 10-11.5 Al
Source: University of Florida

Microstructure
Nominal Composition:
Cu 85.8, Al 10.2, Fe 4.0

Larger View of Micrograph
Largest View of Micrograph

Alloy Family: Aluminum bronzes
Product Form: Cast
Processing: Cast and quenched from 913C
Etchant:
Scale Line Length: ~ 125Microns
Alloy: C95400
Temper:
Material: Aluminum bronze, 10-11.5 Al
Source: University of Florida

Microstructure
Nominal Composition:
Cu 78 min, Al 10.0-11.5, Ni 3.0-5.5, Fe 3.0-5.0, Mn 3.5

Larger View of Micrograph
Largest View of Micrograph

Alloy Family: Aluminum bronzes
Product Form: Cast
Processing: Cast and heat treated
Etchant:
Scale Line Length: ~ 250Microns
Alloy: C95500
Temper:
Material: Nickel-aluminum bronze, 10-11.5 Al, 3-5.5 Ni, Mn 3.5
Source: University of Florida

Microstructure
Nominal Composition:
Cu 81.4, Al 8.9.5, Ni 4.7, Fe 4.0, Mn 1.0

Larger View of Micrograph
Largest View of Micrograph

Alloy Family: Aluminum bronzes
Product Form: Cast
Processing: Annealed at 621C and air cooled
Etchant:
Scale Line Length: ~ 25Microns
Alloy: C95800
Temper:
Material: Nickel-aluminum bronze, 9 Al, 4.5 Ni
Source: University of Florida

Microstructure
Nominal Composition:
Cu 81.4, Al 8.9.5, Ni 4.7, Fe 4.0, Mn 1.0

Larger View of Micrograph
Largest View of Micrograph

Alloy Family: Aluminum bronzes
Product Form: Cast
Processing: Cast and quenched from 857C
Etchant:
Scale Line Length: ~ 25Microns
Alloy: C95800
Temper:
Material: Nickel-aluminum bronze, 9 Al, 4.5 Ni
Source: University of Florida

Microstructure
Nominal Composition:
Cu 81.4, Al 8.9.5, Ni 4.7, Fe 4.0, Mn 1.0

Larger View of Micrograph
Largest View of Micrograph

Alloy Family: Aluminum bronzes
Product Form: Cast
Processing: Cast and quenched from 857C
Etchant:
Scale Line Length: ~ 125Microns
Alloy: C95800
Temper:
Material: Nickel-aluminum bronze, 9 Al, 4.5 Ni
Source: University of Florida