A comparison of methods for predicting the fatigue life of gray cast iron at elevated temperatures

High temperature fatigue life tests were compared with various life assessment methods for gray cast iron in the cylinder liners of marine engines. The plastic strain range-based methods such as the universal slopes method, Mitchell's method, Baumel and Seeger's method, and Ong's method were not predicted well. A method employing tensile energy density, which is defined as the sum of the tensile area of the plastic energy and the elastic energy in the hysteresis loop, was suggested as an improved alternative to the plastic strain range-based methods. The life estimation equation using tensile energy density predicted well within the 3X scatter band at various temperature ranges of the gray cast iron.