Experimental and Numerical Investigation on the Creep Crack Growth in IN718

Creep crack growth (CCG) behaviour of Inconel 718 superalloy are investigated by means of experimental tests and numerical simulation at the temperature of 687 °C. The CCG tests are carried out with different initial values of the stress intensity factor on a standard compact-tension specimen. Creep crack growth are simulated using the finite element code ABAQUS and creep constants obtained from creep tests. C* parameter is used for characterizing CCG behaviour under the steady-state condition. Experimental and numerical results will be compared. Moreover Nikbin, Smith and Webster approach, for the evaluation of the time of crack initiation and the rate of damage accumulation, will be assessed.