An understanding of very high cycle fatigue of metals

Abstract For modern technical applications like cars, trains, and aircrafts, the durability of some components is between 108 and 1010 cycles. However, there are very few experimental results beyond 107 cycles, where the standard fatigue limit is predicted using statistical approaches. Generally, it is said that the probability of failure is given with the Gaussian curve, which is not always true. The S–N curves of metallic materials have been assumed by hyperbolic relationships. However, in some cases the asymptote is not really horizontal. That means that the fatigue strength at 106 cycles is higher that at 108 cycles. Thus, the S–N curve in the gigacycle regime must be determined in order to guarantee the real fatigue strength and safe life of mechanical components. In this paper, the state of the art in this field is summarized through our own results.