Short-life creep rupture characteristics and constitutive model under high stress for a typical low-cost turbine rotor material

To change the current situation of the seriously redundant design of the creep rupture life of low-cost short-life turbine rotor blades, this paper studies the creep rupture characteristics of the typical low-cost material K424 alloy of the integral casting turbine rotor at multiple high stress levels within the near-plastic and plastic ranges at 700°C. Based on the Larson-Miller equation, a creep rupture life equation is established, and a high-precision bivariate creep constitutive model within the high stress range is developed. Compared with the existing parameter methods, it shows obvious superiority, laying a foundation for the refined design of the creep rupture life of low-cost short-life turbine rotor blades.