Papers by Keyword: Ni₃B

Abstract: The phases formed in the wide-gap region brazed with Ni-14Cr-10Co-3.5Al-2.5Ta-2.8B filler metal powder in IN738 superalloy were investigated by electron backscatter diffraction (EBSD). The wide-gap brazing process was carried out in a vacuum of 2×10-5 torr at 1503 K. The region brazed with filler metal powders had a microstructure consisting of two kinds of eutectic colonies, one is Ni solid solution-CrB eutectic and the other is Ni solid solution-Ni3B eutectic. EBSD pattern analysis revealed that the CrB phase had orthorhombic structure with lattice parameters of a=0.297, b=0.786 and c=0.293 nm, and the Ni3B phase had orthorhombic structure with lattice parameters of a=0.439, b=0.522 and c=0.662 nm. The cuboidal-shaped phase precipitated in the Ni solid solution was found to be the γ' (Ni3Al) phase, which had cubic structure with lattice parameter of a=0.357 nm.

Abstract: The phases formed in the wide-gap region brazed with BNi-3 filler metal powder in IN738 superalloy were investigated by electron backscatter diffraction (EBSD). The morphology and chemical composition of the phase were investigated by field emission scanning electron microscopy (FESEM) and Auger electron spectroscopy (AES). The wide-gap region brazed with BNi-3 filler metal had a microstructure consisting of primary Ni3B, binary eutectic of Ni3B-Ni solid solution and ternary eutectic of Ni3B-Ni-Ni3Si structure. EBSD pattern analysis revealed that the Ni3B had orthorhombic structure with lattice parameter of a=0.439, b=0.522 and c=0.662 nm, and the Ni3Si phase had cubic structure with lattice parameter of a=0.350 nm.