the.com/duralumin
the alloy that learned to harden itself, just by sitting around being aluminum.
means Duralumin is a strong, lightweight alloy of aluminum mixed mainly with copper (plus traces of magnesium and manganese) that hardens naturally over time, prized for aircraft and other places where you want metal that's tough but not heavy.
from A blend of two ideas: the 'dur-' part nods to hardness (from Latin 'durus,' hard), while '-alumin' is just aluminum. The name is usually traced to early-20th-century German metallurgy, with the alloy associated with the city of Düren — so one telling is that 'Dür-' honors Düren, another that it simply means 'hard aluminum.' Either way, both threads point to the same boast: this is aluminum that finally toughened up.
- self-strengthening
- Gains strength for days at room temperature after quenching
- zeppelin frame
- Built the rigid skeletons of doomed airships
- named for town
- Coined from Düren, Germany, where it was made
- corrosion problem
- Copper content makes it rust-prone without coatings
- accidental discovery
- Alfred Wilm found the hardening trick by surprise
supermarine spitfire — wwii fighter aircraft fuselage made primarily of duralumin, first flown 1936
de havilland comet — first jet airliner with duralumin fuselage, crashed due to metal fatigue 1954
pan am flying boat — boeing 314 clipper used duralumin hull for transatlantic flights starting 1939