Basic Temper Designations for All Aluminum

F

As Fabricated. Applies to the products of shaping processes in which no special control over thermal conditions or strain-hardening is employed.  For wrought products, there are no mechanical property limits.      

O

Annealed. Applies to wrought products which are annealed to obtain the lowest strength temper.  The O may be followed by a digit other than zero.      

H

Strain-Hardened; wrought products only. Applies to products which have their strength increased by strain-hardening.  This is with or without supplementary thermal treatments to produce some reduction in strength.  The H is always followed by two or more digits.    

H1 (Strain-Hardened Only)  

H2 (Strain-Hardened and Partially Annealed)  

H3 (Strain-Hardened and Stabilized)  

T (Thermally treated to produce stable tempers other than F, O, or H)

Applies to products which are thermally treated, with or without supplementary strain-hardening, to produce stable tempers.  The T is always followed by one or more digits.   

T1

Cooled from and elevated temperature shaping process and naturally aged to a substantially stable condition.    

T2

Cooled from and elevated temperature shaping process, cold worked, and naturally aged to a substantially stable condition.     

T3

Solution heat-treated, cold worked, and naturally aged to a substantially stable condition.    

T4

Solution heat-treated and naturally aged to a substantially stable condition.     T5-  Cooled from and elevated temperature shaping process and then artificially aged.    

T6

Solution heat-treated and then artificially aged.    

T7

Solution heat-treated and then stabilized.    

T8

Solution heat-treated, cold worked, then artificially aged.   

T9 Solution heat-treated, artificially aged, and then cold worked.   

T10

Cooled from and elevated temperature shaping process, cold worked, and then artificially aged.  

T42

Assigned for wrought product test material heat-treated from annealed or F temper, or to wrought products heat-treated from any temper by the user.  The former demonstrates a response to heat-treatment.  Solution heat-treated and naturally aged to a substantially stable condition.    

T51

Stress-Relieved by Stretching.  

T52

Stress-Relieved by Compressing.    

T54

Stress-Relieved by Combined Stretching and Compressing.       

T62

Assigned for wrought product test material heat-treated from annealed or F temper, or to wrought products heat-treated from any temper by the user.  The former demonstrates a response to heat-treatment.  Solution heat-treated and artificially aged to a substantially stable condition.    

W (Solution Heat-Treated)

An unstable temper applicable only to alloys which spontaneously age at room temperature after solution heat-treatment.  This designation is specific only when the period of natural aging is indicated; for example: W 1/2 hr.  This alloy has many uses and typically is used for aircraft skins, cowls, and truck and aircraft structures.