Method for predicting service life of dissimilar material bolt connecting piece by considering low-temperature creep

The invention discloses a method for predicting the service life of a dissimilar material bolt connecting piece by considering low-temperature creep. The method comprises the following steps: 1, acquiring a working temperature range of the connecting piece and an excited load spectrum through a test; 2, determining a bolt model and a pre-tightening force, and calibrating a creep constitutive model; 3, determining a pre-tightening force attenuation rule of the bolt connecting piece through the creep constitutive model; 4, performing stress analysis on the bolt connecting piece to determine a dangerous position; 5, extracting stress distribution of a dangerous position and a bolt thread contact state; 6, substituting the maximum stress into the corresponding S-N stress curve to obtain the residual life of the connecting piece; and 7, calibrating an Iwan model according to the contact state, and obtaining the residual life of the bolt contact surface according to the model. The method can accurately predict the