Fixed Emitting Point Method-An Accelerated Test Program to Determine Fatigue Limit of Automotive Components

The traditional Up And Down Method (UADM) is generally taken as a standard mean to determine the fatigue limit of an automotive component. Its main draw back is extremely time-consuming. A number of other methods can reduce testing time to some extent, but the applications of those results are limited, since they are not comparable with that of UADM. Based on certain preconditions and assumptions, an accelerated testing method, named Fixed Emitting Point Method, has been developed. The applicability and effectiveness of this method have been verified by bending fatigue test of crankshaft and tension-compression fatigue test of connecting rod. Results showed that the errors in the mean fatigue limit values are generally less than 5% while the number of cycles of a test can be reduced by about 90% in comparison with the data given by UADM.