Deformation Stability of GH4033 Superalloy in the Hot Continuous Rolling Process Based on Dynamic Material Model and Finite Element Model

The flow stress behavior of GH4033 superalloy was determined by the hot compression tests at the temperatures of 1 223-1 473 K and the total strains of 0.6 with the strain rates of 0.001-30.0 sby using cylindrical samples.The processing maps based on the dynamic material model (DMM) combined with the corresponding microstructure observations indicate the reasonable processing domain locating at the strain rates of 0.1-1.0 sand the deformation temperature of 1 273-1 423 K.Meanwhile,the numerical simulation based on finite element model (FEM) described the variation of the effective strain,effective strain rate and the temperature for the core node,and unveiled the influence of the hot rolling parameters considering the initial temperature (T) range of 1 223-1 473 K and the first-stand biting velocity (v) range of 0.15-0.35 m·s.Furthermore,the deformation stability of GH4033 superalloy in the round rod hot continuous rolling (HCR) process is described and analyzed by coupling the three-dimensional (3-D) processing map,and the spatial trajectory lines were determined by the numerically simulated temperatures,the strains and the strain rates.Finally,the results show that the hot deformation stability of GH4033 can be achieved by the rolling process parameters located at T=1 423 K and v=0.25 m·s.Additionally,the practical HCR processes as T=1 423 K and v=0.15,0.25,0.35 m·swere operated to verify the influence of the hot rolling parameters on the hot deformation stability by the microstructure observation of the final products.