# 7076 (7076-T61, A97076) Aluminum

7076 aluminum is a 7000-series aluminum alloy: the main alloying addition is zinc and it is formulated for primary forming into wrought products. Cited properties are appropriate for the T61 temper. To achieve this temper, the metal is solution heat-treated and artificially underaged. The degree of underaging is different from T64 and T65. 7076 is the Aluminum Association (AA) designation for this material. In European standards, it will be given as EN AW-7076. A97076 is the UNS number.

It has been in use since 1940, but has only received its standard designation in 1954.

The graph bars on the material properties cards below compare 7076 aluminum to: 7000-series alloys (top), all aluminum alloys (middle), and the entire database (bottom). A full bar means this is the highest value in the relevant set. A half-full bar means it's 50% of the highest, and so on.

## Mechanical Properties

Brinell Hardness

160

Elastic (Young's, Tensile) Modulus

70 *GPa* 10 *x 10 ^{6} psi*

Elongation at Break

6.2 *%*

Fatigue Strength

170 *MPa* 24 *x 10 ^{3} psi*

Poisson's Ratio

0.32

Shear Modulus

27 *GPa* 3.9 *x 10 ^{6} psi*

Shear Strength

310 *MPa* 45 *x 10 ^{3} psi*

Tensile Strength: Ultimate (UTS)

530 *MPa* 77 *x 10 ^{3} psi*

Tensile Strength: Yield (Proof)

460 *MPa* 67 *x 10 ^{3} psi*

## Thermal Properties

Latent Heat of Fusion

380 *J/g*

Maximum Temperature: Mechanical

170 *°C* 340 *°F*

Melting Completion (Liquidus)

630 *°C* 1170 *°F*

Melting Onset (Solidus)

460 *°C* 850 *°F*

Specific Heat Capacity

860 *J/kg-K* 0.21 *BTU/lb-°F*

Thermal Conductivity

140 *W/m-K* 81 *BTU/h-ft-°F*

Thermal Expansion

24 *µm/m-K*

## Electrical Properties

Electrical Conductivity: Equal Volume

35 *% IACS*

Electrical Conductivity: Equal Weight (Specific)

100 *% IACS*

## Otherwise Unclassified Properties

Base Metal Price

9.5 *% relative*

Density

3.0 *g/cm ^{3}* 190

*lb/ft*

^{3}Embodied Carbon

8.0 *kg CO _{2}/kg material*

Embodied Energy

150 *MJ/kg* 63 *x 10 ^{3} BTU/lb*

Embodied Water

1110 *L/kg* 130 *gal/lb*

## Common Calculations

Resilience: Ultimate (Unit Rupture Work)

31 *MJ/m ^{3}*

Resilience: Unit (Modulus of Resilience)

1510 *kJ/m ^{3}*

Stiffness to Weight: Axial

13 *points*

Stiffness to Weight: Bending

45 *points*

Strength to Weight: Axial

49 *points*

Strength to Weight: Bending

48 *points*

Thermal Diffusivity

54 *mm ^{2}/s*

Thermal Shock Resistance

23 *points*

## Alloy Composition

Among wrought aluminum alloys, the composition of 7076 aluminum is notable for containing a comparatively high amount of zinc (Zn). Zinc is used to achieve significant increases in strength, at the cost of increased susceptibility to stress corrosion cracking. Among other things, this limits weldability.

Al | 86.9 to 91.2 | |

Zn | 7.0 to 8.0 | |

Mg | 1.2 to 2.0 | |

Cu | 0.3 to 1.0 | |

Mn | 0.3 to 0.8 | |

Fe | 0 to 0.6 | |

Si | 0 to 0.4 | |

Ti | 0 to 0.2 | |

res. | 0 to 0.15 |

All values are % weight. Ranges represent what is permitted under applicable standards.

## Followup Questions

## Similar Alloys

## Further Reading

ASTM B247: Standard Specification for Aluminum and Aluminum-Alloy Die Forgings, Hand Forgings, and Rolled Ring Forgings

ASM Specialty Handbook: Aluminum and Aluminum Alloys, J. R. Davis (editor), 1993

CRC Materials Science and Engineering Handbook, 4th ed., James F. Shackelford et al. (editors), 2015