What is Aluminum Plate Tempering?
Tempering of aluminum plates refers to the process of altering the mechanical properties of aluminum materials (such as strength, hardness, and elongation) through cold working or heat treatment. There are various types and combinations of tempering processes, including annealing, work hardening, solution heat treatment, and aging treatment. Temper designations are added to the end of the aluminum material designation to indicate its specific characteristics.
Types of Tempering and Symbols:
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F (As fabricated): No special tempering process applied.
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O (Annealed): Heat and cool the aluminum to soften it and improve its workability.
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H (Work-hardened): Increased strength through cold working.
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T (Heat-treated): Strength and stability enhanced through processes such as solution heat treatment and aging.
Examples of T-tempers:
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T3: Solution heat-treated, then cold worked, and naturally aged.
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T4: Solution heat-treated and naturally aged.
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T5: Artificially aged after being cooled from a high-temperature shaping process.
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T6: Solution heat-treated and then artificially aged.
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T7: Solution heat-treated and then overaged.
Common Temper Symbols and Application Examples:
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A5052-H34: Excellent corrosion resistance and formability; used in structural components for ships and automobiles, as well as cans and containers.
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A6061-T6: Good balance of strength and workability; used in items like bicycles and camera tripods.
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A7075-T6: Known as super duralumin; used in aircraft and automotive parts.
Selecting a Temper:
The type of temper is selected based on the material’s application and required properties. For example, if high strength is needed, T6 or H18 temper might be chosen. For better formability, O or H32 temper might be more suitable.
Notes of Caution:
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T6 temper is sensitive to heat and may re-age, so high-temperature processes like welding or painting should be avoided.
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T6 temper has low resistance to stress corrosion cracking, so it should not be used in corrosive environments.
For more detailed information and specific applications, refer to JIS standards or manufacturer documentation.
