My Almega was obviously very seldomly moved. All original parts, no wear on tyres, rims or whatsoever. Bright paint, zero chips. Though the frame developed cracks everywhere.
I heard a Roox post snap when standing in the livingroom.
I undertood alloy does age by time, as does titanium. Steel doesn't. Aluminium will eventually snap sooner or later, but it will.
"Aluminium is real" doesn't rhyme to me
Ok as Industrial design engineer I learned it all, but unfortunately it slipped away after designing toys, trainers for elderly and earplugs.
I will give you a tip: don't buy aluminium frames! especcially the old nice once because they will break, especcially when they have nice collours and the more beautiful the frame is the easier they brake!
ok hope the prices of nice aluminium frames will go down a bit now
That Almega frame must have been of a low alloy degree (like the grisleys) from the 4000 series, cheap. they don't need to be precipitated. Their precipetation hardening already occurs at room temperature, if this process continues for too long there is (translated from dutch) grain growth, the etnic-minority-atoms don't stay in their patern but can slightly move around deteriorating the mechanical properties by grouping just as minorities tend to do in real live. This in combination with a pre stressed frame could cause cracks when just sitting around I guess.
As for the higher quality frames precipitation takes place at a much higher temperature, so if you don't leave your bike in a car cooking in the sun you will be fine. still natural aging continues at a very very slow pass. I never got any info on what time span we must think about, but with airplanes serving for 40years I think my aluminium bikes will outlive me
As for the fatigue, a well engineered frame ensures the strains remain within the fatigue stress boundries, the material will not be streched that far that it will enter this fatigue strain.
Final note: I am NOT a material EXPERT!! just had to learn a little about the terms and stuff to be able to communicate with an material expert. So hope someone can support me. To give you a clue, my book: "Material science and engineering, an introduction" (!) is over 800 pages (at A4 small print, and not that many pictures!) There are maybe four pages about the precipitation of aluminium alloys and not a sentence about long term ageing!