The hot deformation behavior of 00Ci26Mo4 super ferritic stainless steel is studied by the isothermal compression of cylindrical specimens at 1050 ~ 1250°C with the strain rate of 0. 1 ~ 10 s" high temperature compress experiment on Gleeble-3500 simulated machine. By the thermo mechanical parameters of steel simulated by using power function/ exponential function/hyperbolic sine mathematics model

the corresponding hot deformation constitutive is established. The results show that in hot compression process the flow stress decreases with the increase of deformation temperature and in¬creases with the increase of strain rate

and there is no well-defined peak stress in the flow-stress curves. The softening mechanism of 00Cr26Mo4 steel is only dynamic recovery. The constitutive correlation of power fiinction/exponential function/hyperbolic sine mathematics model with 00Cr26Mo4 steel is studied

the results show that the hyperbolic sine mathematics model accords with the rules of the flow stress strain curve of 00Cr26Mo4 super ferritic stainless steel

and using hyperbolic sine mathematics model the 00Cr26Mo4 constitutive equation is established

to get the calculated activation energy of deformation 238. 836 kJ/mol.