Materialermüdung: Aluminium vs. CrMo
Material fatigue: Aluminium vs Chromoly (CrMo)
At the time the aluminium decks, handlebars or forks are new, the strength of these products reaches a potential of 100%.
However, aluminium loses many of its properties over time. After 10 million stress movements, the material loses 65% of its original resistance. That means it becomes three times weaker.
This is also why each deck becomes „softer“ and loses strength, rebound and reactivity after 6 or 8 months.
Unlike human beings the aluminium products can not be „refreshed“. No amounts of vitamins, boosters and other suplements will return an aluminium product back to its original „shape“. It is what it is.
CrMo, on the other hand, does not have this "fatigue" disadvantage. After 10 million cycles, it loses only 35% of its original properties.
This is also why we use steel for suspension springs and not aluminium.
And it's also why handlebars made of CrMo can last a very, very long time, often forever, while handlebars made of aluminum will break one day.
See bellow the chart for aluminium vs CrMo fatigue.
For more information on this topic see the following video (do not forget to turn off the French subtitles) narrated by Kevin Demay.