Research on accelerated test method for fatigue life of cylindrical helical compression

Abstract

In order to accelerate fatigue test, this paper present a technique to transform fatigue lives obtained from specimen tests under high stress levels to the non-tested one under low stress level. This technique is presumably based on the principle of the probability percentiles correspondence of specimen fatigue lives under different cyclic stress levels. The life distribution under low stress level can be derived from the ones under high stress levels. The corresponding conversion process is given, and an example analysis is carried out. The SPSS software is used to calculate the difference of the mean and variance between the equivalent life span and the real life span. The consistency of the mean and variance between the equivalent life span and the real life span is obtained and acceptable. Therefore, spring fatigue tests can be accelerated, that is, low stress life distribution can be derived from the fatigue tests under high stress levels, rather than test it under low stress level.