Fractional derivative Norton–Power creep equation

The creep phenomenon is time-dependent, so a modified fractional derivative Norton-Power creep constitutive equation is proposed in this paper. Both fractional derivative and integer creep constitutive equations fit well with the experimental data. In general, the transient, steady state, and tertiary creep stages are the three stages in which the heat-resistant alloy exhibits creep strain-time curves during creep. It is found that the first and second stages in the process of describing the long-term creep of materials can be well described by the fractional derivative creep equation. This study provides a new method for describing the long-term creep of materials.