1. Basic information of 6061 aluminum alloy
6061 aluminum alloy can be strengthened by heat treatment and has good formability, weldability and machinability. It also maintains good strength after annealing.
The main alloying elements of 6061 aluminum alloy are magnesium and silicon, which form the Mg2Si phase.
If it contains a certain amount of manganese and chromium, it can neutralize the adverse effects of iron. Sometimes a small amount of copper or zinc is added to improve the strength of the alloy without significantly reducing its corrosion resistance.
A small amount of copper is also added in conductive materials to compensate for the adverse effects of titanium and iron on conductivity. Zirconium or titanium can refine grains and control the recrystallization structure. Lead and bismuth can be added to improve machinability.
The melting temperature of 6061 aluminum alloy is between 582-652 ℃, and the old grade is LD30.
Table 1. Chemical composition of 6061 aluminum alloy (GB/T 3190-2008)
| Element | Yes | Faith | Ass | Mn | mg | Cr | Zn | You | Al |
| Happy % | 0.4~0.8 | 0.7 | 0.15~0.40 | 0.15 | 0.8~1.2 | 0.04~0.35 | 0.25 | 0.15 | Remaining |
Table 2. Thickness and mechanical properties of 6061 aluminum alloy sheets and strips
(GB/T 3380-2006)
| Supply status | Sample status | Thickness
mm |
Tensile strength Rm
/MPa |
Elongation at break
% |
| 0
Annealed state |
0 | 0.4~1.5 | ≤150 | 14 |
| 1.5~3.0 | 16 | |||
| 3.6~6.0 | 19 | |||
| 6.0~12.5 | 16 | |||
| 12.5~25 | 16 | |||
| T42 | 0.4~1.5 | 205 | 12 | |
| 1.5~3.0 | 14 | |||
| 3.6~6.0 | 16 | |||
| 6.0~12.5 | 18 | |||
| 12.5~40 | 15 | |||
| T62 | 0.4~1.5 | 290 | 6 | |
| 1.5~3.0 | 7 | |||
| 3.6~6.0 | 10 | |||
| 6.0~12.5 | 9 | |||
| 12.5~40 | 8 | |||
| T4
Natural aging after solution treatment |
T4 | 0.4~1.5 | 205 | 12 |
| 1.5~3.0 | 14 | |||
| 3.6~6.0 | 16 | |||
| 6.0~12.5 | 18 | |||
| T6
Artificial Aging After Solution Treatment |
T6 | 0.4~1.5 | 290 | 6 |
| 1.5~3.0 | 7 | |||
| 3.6~6.0 | 10 | |||
| 6.0~12.5 | 9 | |||
| F
Free machining state |
F | 2.5~150 | – | – |
Table 3. Dimensions and mechanical properties of 6061 aluminum alloy bar
(GB/T 3191-2010)
| Supply status | Sample status | Diameter mm |
Tensile strength Rm/MPa |
Elongation at break % |
| T6 | T6 | ≤150 | 260 | 9 |
| T4 | T4 | 180 | 14 |
2. Typical Applications
Sheets and strips are widely used in various industries such as decoration, packaging, construction, transportation, electronics, aviation, aerospace, armament, etc.
Aluminum for aerospace applications is used to make aircraft skins, body structures, beams, rotors, propellers, oil tanks, wall panels, landing gear brackets, rocket forging rings, spacecraft wall panels, etc.
Transport aluminum is used as a material for structural parts of automobile bodies, subway cars, passenger trains, high-speed trains, as well as for automobile doors and windows, shelves, engine parts, air conditioners, radiators, body panels, wheels, and shipbuilding materials.
Packaging aluminum is mainly used as a metal packaging material in the form of sheets and sheets to make cans, lids, bottles, barrels and packaging sheets. It is widely used in beverages, food, cosmetics, pharmaceuticals, cigarettes, industrial products and other packaging.
Printable aluminum is mainly used in the manufacture of PS boards. Aluminum-based PS plates are a new type of material in the printing industry, used for automated platemaking and printing.
Aluminum for building decoration is mainly used in building structures, doors and windows, ceilings, decorative surfaces, etc., due to its good corrosion resistance, sufficient strength, excellent processing performance and welding properties. Examples include building doors and windows, aluminum curtain wall profiles, aluminum curtain wall panels, pressed plates, stamped plates, color coated aluminum plates, etc.
Aluminum for electronic appliances is mainly used in various areas such as busbars, wire racks, conductors, electrical components, refrigerators, air conditioners, cables, etc.
3. Heat treatment process
Fast annealing:
The heating temperature is 350~410°C, depending on the effective thickness of the material, the retention time is between 30~120 minutes, and cooling can be done in air or water.
High temperature annealing:
The heating temperature is 350~500°C, when the thickness of the finished product is ≥6mm, the holding time is 10~30 minutes, and when it is <6mm, heat until the material is fully penetrated and then cooled in air.
Low Temperature Annealing:
The heating temperature is 150~250°C, with a waiting time of 2~3 hours and cooling can be done in air or water.
