車架材質vs車架壽命

Steel and titanium only fatigue if loads abnormal (possibly unheard of) for cycling are placed upon them. Where aluminum fatigues at any load level, ie. every pedal stroke contributes to the frames death. As for the "all metal frames fatigue and eventually fail" statement, that is not a realistic view to take. How long are you going to live? Steel and titanium are going to outlast you by far, and titanium will outlast your children. Ultra-violet radiation can weaken the breaking load of Carbon.

鋁材質的特性是金屬疲勞閥值超低，幾乎所有受到的應力都會累積。

相對來說，鋼材質也是會金屬疲勞，不過閥值較高，在彈性範圍內，幾乎都會回復，不太會累積應力。(所以才有人說鋼管車可以傳家！不過，保存不好，可能會鏽掉！)

至於碳纖材質，就算不疲勞，也是會直接老化(紫外線)，然後就不治了。

鋁材及鋼材的金屬疲勞特性受時間影響不大，不太會自己掛掉！