Stress rupture characteristics of Inconel 718 alloy for ramjet combustor

To evaluate the accelerated creep phenomena for ramjet combustor, the stress rupture tests for Inconel 718 alloy were performed at a temperature range of 649–760 °C and a stress range of 381–1093 MPa. The stress exponent, n, under the given conditions was obtained. Also, the activation energy, ΔH, was calculated from the experimental results. An empirical formula of accelerated creep rate for Inconel 718 alloy was calculated by computer simulation. The accelerated creep life of Inconel 718 alloy was evaluated by using Larson–Miller parameter.