In order to solve the problems such as piston crown burning and cracking in the actual operation of marine diesel engines

a finite element method was used to perform the thermomechanical coupling simulation analysis of the stress field and temperature field of a piston under the combined action of periodic burst pressure

inertial force and thermal stress. These analysis results were then inputted into a BASIC module of the fatigue analysis software（FEMAFT) to analyze the safety factor of each part of the piston for finding areas prone to fatigue failure

and the fatigue life of the piston was predicted according to the linear fatigue cumulative failure rate criterion（Miner). Then

the fatigue damage accumulation theory（Aeran) was used to analyze the fatigue failure process of the piston under thermomechanical coupling conditions. And from this

an accelerated fatigue model of the piston under different loads was established to determine the relationship between the number of piston operating cycles and the piston damage evolution.