Technology/Aluminum Technology

1. Type of Aluminum Alloy :
aluminum alloy is a chemical composition where other elements are added to pure aluminum in order to enhance its properties, primarily to increase its strength. These other elements include iron, silicon, copper, magnesium, manganese and zinc at levels that combined may make up as much as 15 percent of the alloy by weight.  Alloys are assigned a four-digit number, in which the first digit identifies a general class, or series, characterized by its main alloying elements.
 
Heat-Treatable Alloys Description
2xxx Al-Cu-Mg  Alloy --ex. 2011, 2014, 2024 ... 
6xxx Al-Mg-Si Alloy -- ex. 6061, 6063 ... 
7xxx Al-Zn-Mg Alloy-- ex. 7075 ... 
 
Non Heat-Treatable Alloys Aluminum Alloy Series
1xxx Pure Aluminum -- ex. 1050, 1070 ...
3xxx Al-Mn  Alloy -- ex. 3003 ...
4xxx Al-Si  Alloy -- ex. 4032 ...
5xxx Al-Mg  Alloy -- ex. 5052, 5083 ...

2. Aluminum Temper Designations :
The temper designation follows the alloy code.
 
Aluminum Temper Description
F As Fabricated: No special control has been performed to the heat treatment or strain hardening after the shaping process such as casting, hot working, or cold working.
O Annealed: This is the lowest strength, highest ductility temper.
H Strain-Hardened: Applies to wrought products which are strengthened by cold-rolling or cold-working.
W Solution Heat Treated : This is seldom encountered because it is an unstable temper that applies only to alloys that spontaneously age at ambient temperature after heat treatment.
T Heat Treated - Used for products that have been strengthened by heat treatment, with or without subsequent strain hardening.  


3. Heat Treating T Temper Codes :
Alloys in the 2xxx, 6xxx and 7xxx groups can be strengthened by a heat treatment process. The aluminum is heat treated by carrying out a solution treatment process, in which the metal is heated to an elevated temperature followed by rapid cooling, then a precipitation hardening process (or “aging” process). The tempers are designated by –T followed by a digit.
 
Temper Code Description
T1 Cooled from an elevated temperature shaping process and naturally aged to a substantially stable condition.
T2 Cooled from an 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 an elevated temperature shaping process then artificially aged.
T6 Solution heat treated then artificially aged.
T7 Solution heat treated then overaged/stabilized.
T8 Solution heat treated, cold worked, then artificially aged.
T9 Solution heat treated, artificially aged, then cold worked.
T10 Cooled from an elevated temperature shaping process, cold worked, then artificially aged.
TX51 Solution heat treated, stress relieved by stretching.
TX52 Solution heat treated, stress-relieved by compressing.
TX53 Stress-relieved by thermal treatment.