The microstructure of Au-doped NiAl-Cr(Mo) eutectic and its mechanical properties

The effect of various gold content on the microstructure and compressive behavior of NiAl-28Cr-6Mo eutectic alloy has been investigated by using a combination of SEM, XRD, TEM and compression tests. It is concluded that the addition with less than 0.5% Au causes the changed microstructure of the eutectic alloys, which includes the lamellar refinement, fragment of Cr(Mo) phase, disappearance of Cr(Mo) phase' radial orientation in cell interior, while 1% Au addition makes the alloy severely deviate from eutectic composition and formed new phase α-AlAu2. The high-temperature compressive properties have been significant affected due to the changed microstructure, while the room temperature compressive properties have not attained distinct change.