INFLUENCE OF HOT WORKING PROCESS ON MICRO STRUCTURES OF SUPERALLOY GH4586

The effects of temperature, strain rate and plastic strain on flow behavior and mi crostructures of GH4586 wrought superalloy were investigated by compressive deformation performed on MTS machine at deformation temperatures of 950 to 1150 ℃ and strain rates of 0.001 to 1 s-1. The results show that the flow stress increases drastically with the decrease of deformation temperature and the increase of strain rate. Dynamic recrystallization process can be effectively promoted by increasing deformation temperature. When deformation temperature is higher than 1100 ℃, completely recrystallized microstructures can be obtained with engineering strain of 30%, while when the temperature is lower than 1050 ℃, dynamic recrystallization does not occur with engineering strain up to 40%. Grain size of annealed microstructures increases with the increase of deformation temperature. Ideal plasticity and resultant microstructures can be achieved by effective control of deformation temperature.