Effect of accelerating voltage on planar and axial channeling in ordered intermetallic compounds

The ternary site occupancy of two alloys, vanadium in NiAl + V and hafnium in nickel-rich, boron doped Ni₃Al + Hf, was determined by ALCHEMI, or atom location by channeling enhanced microanalysis. Vanadium exhibited a preference for the aluminum sublattice in NiAl, and hafnium preferentially occupied the aluminum sites in Ni₃Al. Spectra were acquired over a range of accelerating voltages from 80 kV to 200 kV. Delocalization effects were observed to increase as the accelerating voltage increased, which thus reduces the accuracy of the ALCHEMI data. For NiAl + V, both planar and axial channeling were performed, and delocalization effects were greater for axial channeling, further reducing the accuracy of the ALCHEMI data.