A new prediction model of steady state stress based on the influence of the chemical composition for nickel-base superalloys

By means of series Gleeble 1500D hot compression tests, the influences of primary alloying elements on steady state stress for 16 type wrought nickel-base superalloys were systematically investigated. Meanwhile, a general equation between the steady state stress and the composition variant was put forward through the activation energy Q and the Zener–Hollomon parameter based on the hyperbolic sine model. The results indicated that different alloying elements influence the activation energy Q to different extent, an exponential function can depicted the relationship between the activation energy and the content variant of common alloying elements in these alloys such as Cr, W, Mo, Ti, Nb and Al satisfactorily. The new model can predict the steady state stress at any temperature and strain rate for any similar nickel-base alloys within the typical hot working range. Furthermore, the mechanism of the chemical composition's influence on deformation behaviors was investigated, and the general characteristics of stress–strain curves for nickel-base alloys were also discussed in this paper.