EVOLUTION OF THE MICROSTRUCTURE IN ALLOY 800HT UNDER HIGH-TEMPERATURECREEP LOAD

In the present work the microstructural evolution under isothermal and high temperature creep conditions is studied for the iron-base-alloy Incoloy Alloy 800HT (X10 NiCrAlTi 32 20 HT) at temperatures of 800 deg rees C and 900 degrees C and stresses of 70 MPa and 45 MPa resp. To de scribe the microstructure changes under creep stress loading and const ant test temperature the dislocation density, particle size and mean p laner interparticle spacing where investigated using transmission elec tron microscopy. The results of the dislocation density and particle m orphology measurements are compared and discussed in the contest of cr eep deformation, heat treatment conditions and creep behaviour.