Aluminum Metallurgy
Aluminum has a FCC lattice structure. It is very malleable. Its tensile strength is around 28 MPa and the modulus of elasticity for aluminum is approximately 69 GPa.
Aluminum Alloys: Can be as much as 15 times stronger than pure aluminum, through the addition of small amounts of alloying element, strain hardening by cold working, and heat treatment.
Common Alloys: Copper, manganese, zinc, silicon, magnesium.
Cold Working: Increases strength by causing a disruption of the slip planes in the material that resulted from production process.
Alloy Designation System: Classification starts by separating the product according to its production method (either casting or wrought methods).
The designation system for wrought alloys consists of a four-digit code. The first digit indicates the alloy series. The second digit, if different from 0, indicates a modification in the basic alloy. The third and fourth digits identify the specific alloy in the series; these digits are arbitrarily assigned, except for the 1xxx series, in which the final two digits indicate the minimum aluminum content.
For the 1xxx series, the aluminum content is 99% plus the last two digits of the code, expressed as a decimal fraction. An example would be 1060, which contains a minimum aluminum content of 99.60%.
Cast alloys are assigned a three-digit number followed by one digit after a decimal point. The first digit represents the alloy series. The second and third digits are arbitrarily assigned to identify specific alloys.
Temper Treatments: Specifications of an aluminum material must include the manner in which the product was tempered (either strong (heat-treatable) or common (non-heat-treatable)).
Strong Alloys: Contain elements, constituents that have a considerable solid solubility at elevated temperatures and limited solubility at lower temperatures.
Common Alloys: Contain elements that remain substantially in solid solution or that form insoluble constituents.
Aluminum has a FCC lattice structure. It is very malleable. Its tensile strength is around 28 MPa and the modulus of elasticity for aluminum is approximately 69 GPa.
Aluminum Alloys: Can be as much as 15 times stronger than pure aluminum, through the addition of small amounts of alloying element, strain hardening by cold working, and heat treatment.
Common Alloys: Copper, manganese, zinc, silicon, magnesium.
Cold Working: Increases strength by causing a disruption of the slip planes in the material that resulted from production process.
Alloy Designation System: Classification starts by separating the product according to its production method (either casting or wrought methods).
The designation system for wrought alloys consists of a four-digit code. The first digit indicates the alloy series. The second digit, if different from 0, indicates a modification in the basic alloy. The third and fourth digits identify the specific alloy in the series; these digits are arbitrarily assigned, except for the 1xxx series, in which the final two digits indicate the minimum aluminum content.
For the 1xxx series, the aluminum content is 99% plus the last two digits of the code, expressed as a decimal fraction. An example would be 1060, which contains a minimum aluminum content of 99.60%.
Cast alloys are assigned a three-digit number followed by one digit after a decimal point. The first digit represents the alloy series. The second and third digits are arbitrarily assigned to identify specific alloys.
Temper Treatments: Specifications of an aluminum material must include the manner in which the product was tempered (either strong (heat-treatable) or common (non-heat-treatable)).
Strong Alloys: Contain elements, constituents that have a considerable solid solubility at elevated temperatures and limited solubility at lower temperatures.
Common Alloys: Contain elements that remain substantially in solid solution or that form insoluble constituents.
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