New opportunities for accelerated testing with increased load

Breakage from metal fatigue is one of the main reasons for the failure of machines and structures. We have taken accelerated tests with an increasing load as a starting point and proposed formulas for the implementation of calculations.As a result it is possible to obtain the region of the part's behavior under high loads from data on a known fatigue curve (5–6 samples) and even from the data on two samples tested.Shown here are our proposed methods for calculating the fatigue limit under stepwise and stepless loading. Now the fatigue limit can be determined by one value of the amount of accumulated damage. This allowed to eliminate graphical construction simplified and accelerated the process of selective control of the fatigue limit. Therefore these methods can be recommended for assessing the limit of fatigue strength. The results obtained make it possible to predict a virtual field of fatigue curves variation as a result of two samples testing or by using published literature data and enable quick selection of the material design and method for manufacturing the part.