Creep Characterization of Ni Based Superalloy IN 792 Using the 4 and 6 خ¸ Projection Method

Abstract

This paper studies the accuracy of a technique which is capable of predicting and modeling a wide range of creep life in Nibased superalloys. The خ¸projection method was applied to characterize the creep behavior of the Nibased superalloy IN792 at 800 آ°C. Constant load creep tests have been carried out over a wide range of loads at the constant operating temperature. Creep curves were fitted using either 4خ¸ or 6خ¸ equation by the use of a nonlinear leastsquare technique. The results showed that both 4and 6خ¸ projection parameters revealed a good linearity as a function of stress. Comparison of experimental creep curves with those predicted using both of the utilized خ¸projection techniques showed that the techniques fit the experimental data at high strain values very well while the 6خ¸ approach describes much better the creep curves at low strain region.