Tension and creep design stresses of the “Hastelloy-X” alloy for high-temperature gas cooled reactors

To provide the design data for the Hastelloy-X alloy, the tensile and creep test data was obtained experimentally, and a number of creep data was also collected through literature surveys. All of the experimental and collected data was combined to determine a minimum design value for a tensile stress and to predict a long-term life for a creep rupture time. The design yield and ultimate tensile stress curves for the Hastelloy-X alloy were determined by a best fitting all of the data up to 1000 °C. Creep master curves based on the Larson–Miller parameter were obtained for the standard deviations of 1σ, 2σ and 3σ. The creep-rupture life for up to 105 h was predicted for the Hastelloy-X alloy.