Constructing Thermal Deformation Constitutive Equation with Temperature Jumping for Plain Carbon Steel Based on Fast Isothermal Compression Test

Traditional and modified (with temperature jumping) thermal deformation constitutive equations were constructed by flow stress curves and temperature curve obtained from fast isothermal compression test based on Gleeble3500 thermal simulation tester, and the measured results were compared with the results obtained by the constitutive equations. The temperature jumping of plain carbon steel during thermal compression and the effect of temperature jumping on precision of the constitutive equation were studied. The results show that the temperature jumping caused by plastic work deviated from the given values, and the temperature raised caused by heat trasformed from plastic work was linear ship with the ture strain, and the linear coefficient was connected with the given deformation temperature during the fast compression. The precipitated accuracy of the constitutive equations with temperature jumping was higher than that of the traditional constitutive equation.