A thermo-mechanical coupling.finite element model was built to investigate the inertia friction welding of GH4169 bars. The remeshing and map solution techniques were adopted. Ttle whole welding process was investigated by adopting an innovative heat generation model and the flywheel rotational speed measured via the experiment. The simulated evolution of axial shortening shows a good agreement with the experiment. In addition, extensive .strain concentration presents in the interface and flash, and the largest ,strain exists near the flash root. Moreover, an intere.sting thermal reflux phenomenon during the cooling stage was found.
By monitoring the line voltage and current of the driving motor during linear friction welding （ LFW） of GH4169 superalloy, the frictional power of the rubbing interface between two components to be joined was detected. The data was recorded by a data acquisition card and processed by the LabVIEW software. By analyzing the evolution of frictional power, the joint formation mechanism was discussed. The curves of the measured basic variables （frictional power, axial shortening, interfacial temperature and axial pressure） reflected the characteristics of the LFW process and offered an effective way for welding parameter optimization.
