The surface microstructure of Ni–W alloy tapes, which are used as substrates to form films of high-temperature superconductors and photovoltaic devices, has been studied. Several samples of a Ni95W5 tape (Evico) annealed under different conditions were analyzed using scanning electron microscopy, energy-dispersive X-ray microanalysis, electron diffraction, and electron energy-loss spectroscopy. NiWO4 precipitates are found on the surface of annealed samples. The growth of precipitates at a temperature of 950°С is accompanied by the formation of pores on the surface or under an oxide film. Depressions with a wedge-shaped profile are found at the grain boundaries. Annealing in a reducing atmosphere using a specially prepared chamber allows one to form a surface free of nickel tungstate precipitates.
Original language | English |
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Pages (from-to) | 1002-1007 |
Number of pages | 6 |
Journal | Crystallography Reports |
Volume | 61 |
Issue number | 6 |
DOIs | |
State | Published - 1 Nov 2016 |
Externally published | Yes |
ID: 88202502