Study on hot deformation behavior of as-cast 22%W high-density steel

The hot deformation behavior and microstructure evolution of newly developed as-cast high-density steel were investigated by performing hot compression tests in the temperature range of 1000–1200 °C and strain rate range of 0.001–10 s⁻¹. Flow stress data using hyperbolic sine equation was performed to obtain the constitutive relationship and the activation energy for the hot deformation of the steel. The novel steel shows higher activation energy due to the high tungsten content. The workability of as-cast steel was studied through processing map approach based on dynamic material model. When the strain is 0.8, the optimum procession condition is around 1160 °C/0.001 s⁻¹ with a peak efficiency of 0.52. With the increase of temperature and decrease of strain rate, the degree of dynamic recrystallization increases.