The thermal stability of Ni-Mo and Ni-W thin films: Solute segregation and planar faults

The microstructure and segregation behaviour of sputter-deposited Ni–Mo and Ni–W films were investigated by transmission electron microscopy and X-ray diffraction using laboratory and synchrotron sources. Whereas half of the Mo content segregated already during deposition, W segregation was kinetically hindered. During thermal loading up to 850 K, segregation of Mo and W could be observed. The microstructure of Ni–W films was found to be much more thermally stable than that of Ni–Mo films.