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A series of tests for low cycle fatigue are conducted for Mod.9Cr-1Moferrite steel under multiaxial loading at 550℃. The effect of strain multiaxiality on thefatigue life under proportional loading is considered by defining the principal strainratio. The cyclic properties under different strain paths and strain amplitudes for thismaterial are discussed. It is shown that the softening property is observed at hightemperature for all the strain paths. The effect of loading path on the softening propertyis more prominent than that of strain amplitude. The fatigue life is predicted byequivalent strain approach, energy approach, and critical plane approach. It can beconcluded that the results for equivalent strain approach are too conservative, theresults for energy method, i.e. LKN, are excellent. The prediction lives of SWTapproach are nonconservative for the torsion path, but on the whole the prediction livesare acceptable. The prediction results for FS and KBM approach are satisfying and theprediction results for CXH approach are better than that of SWT.