But steel alloys subjected to cyclic stress levels below their endurance limit rarely fail as a result of fatigue.
但是在钢铁合金的耐用度限制下，作为疲劳的结果，它们经受周期压力级别很少失灵。
2
Fatigue strength is less than static stress strength such as elasticity limit, yield strength.
疲劳强度低于弹性极限或屈服强度等静应力强度。
3
The primary cause of breakage is that the dynamic stress exceeded the allowable fatiguelimit of the beam, and another cause is that the structure of the beam is unreasonable.