Aluminium Alloy - ASTM & FED-QQ - QQ-A-250/12 T651 Plate

QQ-A-250/12 T651 Plate

A high strength aerospace aluminium alloy with, depending upon temper, Yield Strength of up to 54ksi (370 MPa) and Tensile Strength of up to 67 ksi (460 MPa)

Chemical Composition

Spec: SAE AMS QQ-A-250/12

Alloy QQ A 250/12

Chemical Element % Present
Silicon (Si) 0.0 - 0.40
Iron (Fe) 0.0 - 0.50
Copper (Cu) 1.20 - 2.00
Manganese (Mn) 0.0 - 0.30
Chromium (Cr) 0.18 - 0.28
Magnesium (Mg) 2.10 - 2.90
Zinc (Zn) 5.10 - 6.10
Titanium (Ti) 0.0 - 0.20
Other (Each) 0.0 - 0.05
Others (Total) 0.0 - 0.15
Aluminium (Al) Balance


Physical PropertyValue
Density 2.81 g/cm³
Melting Point 635 °C
Thermal Expansion 23.5 x10^-6 /K
Modulus of Elasticity 72 GPa
Thermal Conductivity 134-160 W/m.K
Electrical Resistivity 40 % IACS
'Typical' Physical Properties are given

Alloy Designations

Aluminium alloy QQ-A-250/12 has similarities to the following standard designations and specifications but may not be a direct equivalent:

AMS 4044, Alloy 7075, UNS A97075

Temper Types

Alloy QQ-A-250/12 is supplied in a wide range of tempers:

  • O - Soft
  • T351 - Solution heat treated then stress relieved by stretching. Equivalent to T4 condition.
  • T6 - Solution heat treated and artificially aged
  • T62 - Solution heat treated then artificially aged by the user
  • T651 - Solution heat treated, stress relieved by stretching then artificially aged
  • T6510 - Solution heat treated and stress-relieved by stretching then artificially aged with no straightening after aging - Equivalent to T4 condition
  • T73 - Solution heat treated then specially artificially aged for resistance to stress corrosion
  • T7351 - Solution heat treatment then specially artifically aged for resistance to stress corrosion.

Supplied Forms

Alloy QQ-A-250/12 T651 is supplied in sheet and plate

  • Sheet
  • Plate

Mechanical Properties

The Mechanical Properties given are for Plate in the T651 temper

Thickness (mm)Proof Strength (Min)Tensile Strength (Min)Elongation % (Min)
Over 6.3 up to & incl. 12.64625389
12.7 up to & incl. 25.44695387
Over 25.4 up to & incl. 50.84625316
Over 50.8 up to & incl. 63.54415245
Over 63.5 up to & incl. 76.24214965
Over 76.2 up to & incl. 88.94004905
Over 88.9 up to & incl. 101.63724623
Download PDF Version

Datasheet Search

Last Datasheet Revision

17 January 2014


This Data is indicative only and as such is not to be relied upon in place of the full specification. In particular, mechanical property requirements vary widely with temper, product and product dimensions. All information is based on our present knowledge and is given in good faith. No liability will be accepted by the Company in respect of any action taken by any third party in reliance thereon.

Please note that the 'Datasheet Update' date shown above is no guarantee of accuracy or whether the datasheet is up to date.

The information provided in this datasheet has been drawn from various recognised sources, including EN Standards, recognised industry references (printed & online) and manufacturers’ data. No guarantee is given that the information is from the latest issue of those sources or about the accuracy of those sources.

Material supplied by the Company may vary significantly from this data, but will conform to all relevant and applicable standards.

As the products detailed may be used for a wide variety of purposes and as the Company has no control over their use; the Company specifically excludes all conditions or warranties expressed or implied by statute or otherwise as to dimensions, properties and/or fitness for any particular purpose, whether expressed or implied.

Advice given by the Company to any third party is given for that party’s assistance only and without liability on the part of the Company. All transactions are subject to the Company’s current Conditions of Sale. The extent of the Company’s liabilities to any customer is clearly set out in those Conditions; a copy of which is available on request.