Preparation of Inoculants Used in Superalloy and Analysis of the Atomic Matching Models

The mechanisms of grain refinement were investigated on two kinds of grain refiners used in Ni-Fe based superalloys and complete atomic matching modes were constructed in this study. It is found that there are at least three matching crystal planes having the small lattice disregistry between the refiner and the nucleated phase, which can lead to grain refinement of gamma matrix. The results indicate that the (0001), (01-10) planes of CrFeNb have a fine crystallographic matching relationship with the (111), (110) planes of gamma matrix. The disregistry of (0001)(CrFeNb)//(111)(gamma), (01 (1) over bar0)(CrFeNb)//(111)(gamma) and (01 (1) over bar0)(CrFeNb)//(110)(gamma) is 3.34%, 6.60% and 5.90%, respectively. The (0001), (01 (1) over bar0) planes of Co3FeNb2 and (111), (110) planes of gamma matrix also have this relationship. The disregistry of (0001)(Co3FeNb2)//(111)(gamma), (0001)(Co3FeNb2)//(110)(gamma), (01 (1) over bar0)(Co3FeNb2)//(111)(gamma) and (01 (1) over bar0)(Co3FeNb2)//(110)(gamma) is 4.45%, 9.35%, 8.38% and 6.12%, respectively.