Abstract: A conductive screw of T2 Cu in the generator of a thermal power plant fractured during operation, causing the failure of the generator. Combined with the operation conditions of the equipment, macroscopic observation, chemical composition analysis, metallographic analysis, scanning electron microscopy, energy spectrum micro-area composition analysis, performance testing and other technical means were used to comprehensively analyze and characterize the failed component. The quality of the conductive screw was assessed according to the standard, and combined with the production and processing technology of the conductive screw and its operation environment, the failure cause of the screw was analyzed. Then simulation experiments were carried out to verify the correctness of the conclusion. The results show that the failure of the screw is mainly due to the coarse grains and lower strength. During long-term service, creep intergranular brittle fracture occurred. Finally, corresponding improvement suggestions were put forward.