Experimental study on the high temperature stress rupture of a single crystal superalloy NASA IR100

The microstructure and high temperature stress rupture properties of NASA IR100 single crystals under both as-cast and heat treating condition were investigated through using the scanning electron microscope to observe its fracture morphology. It was found that the formation of creep-voids initiates from the γ-γ' eutectic, W-riched phase, porosity and γ-γ' interfaces; and the course of high temperature stress rupture of single crystal superalloy is the one that the creep voids grow into dimples under the combined action of both temperature and stress, then unite with each other through the tearing edges.