Curated with aloha by
Ted Mooney, P.E. RET
The authoritative public forum
for Metal Finishing 1989-2025
-----
Aluminum Alloys 75S(T) and 79S and the Avro Arrow
Q. I am trying to find the material properties of two aluminum alloys that were used in the Avro Arrow: 1) 75S(T) and 2) 79S. Any ideas?
Mike Hildebrand- Ottawa, Ontario, Canada
2001
A. ike, those sound like rather old designations within a particular specification: and my best guess would be the British Standard series of specifications that dealt with aluminum (or "aluminium"), BS 1470, BS 1471, BS 1474, etc. I don't find either of the ones you mentioned listed in my usual books of Equivalent Specifications so I likely won't be of help. My next step would be to contact a customer service metallurgist at Alcan or Alcoa in the UK, and see if they might remember those designations, and to what four digit Aluminum Association designation they might correspond.
Good luck!
Lee Gearhart
metallurgist - E. Aurora, New York
2001
2001
A. 75S is an Alcan notation which is equivalent to ISO Al-Zn6MgCu. Chemical composition in wt %.
Zn 5.1-6.1
Mg 2.1-2.9
Cu 1.2-2.0
Cr 0.18-0.35
Fe 0.50 max.
Si 0.40 max.
Mn 0.30 max.
Ti 0.20 max.
Other 0.05 max each - total 0.15
0 condition UTS 21.8 kg/mm2 - 0.2% Proof stress 12.7 kg/mm2
T6 temper UTS 54.9 kg/mm2 - 0.2% Proof stress 49.2 kg/mm2
I have no info on the other alloy.
Timur Ulucakaluminum extrusions & finishing - Istanbul, Turkey
A. I believe UNS 7049 is a better suited equivalent to 75-S alloy.
Scott McClelland- Victoria, BC, Canada
2006
Q, A, or Comment on THIS thread -or- Start a NEW Thread