7075 aluminium alloy

7075 is an aluminium alloy, with zinc as the alloying element. It is strong, with good fatigue strength and average machinability, but is not weldable and has less resistance to corrosion than many other alloys. Its relatively high cost limits its use to applications where cheaper alloys are not suitable.

It is commonly produced in several heat temper grades, 7075-O, 7075-T6, 7075-T651.

History

The first 7075 was developed by Japanese company Sumitomo Metal in 1936. [ [http://www.aluminum.or.jp/basic/alumi-sangyo/hf00.html JAPAN ALUMINIUM ASSOCIATION] ] (Japanese)] 7075 was used for the Zero fighter's air frame of the Imperial Japanese Navy in pre-war times.

Basic properties

As with all aluminium alloys, 7075 has a specific gravity of 2.73 (0.098 lb/cubic inch).

Mechanical properties

The mechanical properties of 7075 depend greatly on the temper of the material. [http://www.alcoa.com/mill_products/catalog/pdf/alloy7075techsheet.pdf Alcoa 7075 data sheet] (pdf), accessed October 13, 2006]

7075-0

Un-heat-treated 7075 (7075-0 temper) has maximum tensile strength no more than 40,000 psi (276 MPa), and maximum yield strength no more than 21,000 psi (145 MPa). The material has elongation (stretch before ultimate failure) of 9-10%.

7075-T6

[http://www.alcoa.com/mill_products/catalog/pdf/alloy7075techsheet.pdf 7075 tech sheet] T6 temper 7075 has an ultimate tensile strength of 74,000 - 78,000 psi (510 - 538 MPa) and yield strength of at least 63,000 - 69,000 psi (434-476 MPa). It has elongation of 5-8%.

7075-T651

T651 temper 7075 has an ultimate tensile strength of at least 67,000 - 78,000 psi (462 - 538 MPa) and yield strength of 54,000 - 67,000 psi (372-462 MPa). It has elongation of 3-9%.

Uses

7075 is widely used for construction of aircraft structures, such as wings and fuselages. [http://www.aircraftspruce.com/catalog/mepages/aluminfo.php Aluminum Information at aircraftspruce.com] , accessed October 13, 2006] Its strength and light weight are also desirable in other fields. Rock climbing equipment and bicycle components are commonly made from 7075 aluminium alloy. The bicycle industry is also using 7005 and 6061 aluminium alloys.

Trade names

7075 has been sold under various trade names including Zicral.also Fortal Constructal

References

See also

* Aluminium alloy

References