7075 aluminium alloy
| A7075 T6 | |
|---|---|
| Physical properties | |
| Density (ρ) | 2.81 g/cm3 (0.102 lb/cu in) |
| Mechanical properties | |
| Young's modulus (E) | 71.7 GPa (10,400 ksi) |
| Tensile strength (σt) | 572 MPa (83.0 ksi) |
| Elongation (ε) at break | 11% |
| Poisson's ratio (ν) | 0.33 |
| Hardness—Rockwell | 87 HRB |
| Thermal properties | |
| Melting temperature (Tm) | 477 °C (891 °F) |
| Thermal conductivity (k) | 130–150 W/m*K |
| Linear thermal expansion coefficient (α) | 2.36*10−5 K−1 |
| Specific heat capacity (c) | 714.8 J/kg*K |
| Electrical properties | |
| Volume resistivity (ρ) | 51.5 nOhm*m |
7075 aluminium alloy (AA7075) is an aluminium alloy with zinc as the primary alloying element. It has excellent mechanical properties and exhibits good ductility, high strength, toughness, and good resistance to fatigue. It is more susceptible to embrittlement than many other aluminium alloys because of microsegregation, but has significantly better corrosion resistance than the alloys from the 2000 series. It is one of the most commonly used aluminium alloys for highly stressed structural applications and has been extensively used in aircraft structural parts.
7075 aluminium alloy's composition roughly includes 5.6–6.1% zinc, 2.1–2.5% magnesium, 1.2–1.6% copper, and less than a half percent of silicon, iron, manganese, titanium, chromium, and other metals. It is produced in many tempers, some of which are 7075-0, 7075-T6, 7075-T651.
The first 7075 was developed in secret by a Japanese company, Sumitomo Metal, in 1935, and eventually used for airframe production in the Imperial Japanese Navy. 7075 was reverse engineered by Alcoa in 1943, after examining a captured Japanese aircraft. 7075 was standardized for aerospace use in 1945.