Effect of Titanium on the Partition Behavior of Alloying Elements in Single Crystal Superalloys Containing Rhenium

Abstract

Effect of Ti on the microstructure evolution and element partition in  and  phase after heat treatment were investigated in single crystal superalloy with different contents of Ti addition (0, 0.5, 1.0wt.%) by using scanning electron microscope (SEM) and 3-D atom probe (3DAP). The results show that with the increase of titanium addition, the size of r’phase increase after full heat treatment and the amount of TCP phase increase during long term thermal exposure. Ti makes more r matrix forming elements such Re, W, Cr, Co, Mo partition into r matrix and more Ni element distribute to the r’phase. The electronic structure and binding energy of a number of Ni+X alloy systems were calculated using the discrete variational cluster method based on the local density approximation of the density functional theory