Kinetics and Mechanism of the Reduction of Nickel Oxide in Aligned Nickel Oxide-Zirconia and Nickel Oxide-Yttria Eutectic Structures

1990 ◽  
Vol 73 (6) ◽  
pp. 1524-1528 ◽  
Author(s):  
Guy Dhalenne ◽  
Beatrice Bonvalot ◽  
Alexandre Revcolevschi ◽  
Francis Millot
2019 ◽  
Vol 123 (35) ◽  
pp. 21513-21521 ◽  
Author(s):  
Suren L. Kharatyan ◽  
Hakob A. Chatilyan ◽  
Khachatur V. Manukyan

1995 ◽  
Vol 35 (9) ◽  
pp. 1043-1049 ◽  
Author(s):  
M. I. Nasr ◽  
A. A. Omar ◽  
M. H. Khedr ◽  
A. A. El-Geassy

Author(s):  
M. T. Tinker ◽  
L. W. Hobbs

There is considerable technological interest in oxidation of nickel because of the importance of nickel-base superalloys in high-temperature oxidizing environments. NiO scales on nickel grow classically, by outward diffusion of nickel through the scale, and are among the most studied of oxidation systems. We report here the first extensive characterization by transmission electron microscopy of nickel oxide scales formed on bulk nickel substrates and sectioned both parallel and transversely to the Ni/NiO interface.Electrochemically-polished nickel sheet of 99.995% purity was oxidized at 1273 K in 0.1 MPa oxygen partial pressure for times between 5 s and 25 h. Parallel sections were produced using a combination of electropolishing of the nickel substrate and ion-beam thinning of the scale to any desired depth in the scale. Transverse sections were prepared by encasing stacked strips of oxidized nickel sheet in epoxy resin, sectioning transversely and ion-beam thinning until thin area spanning one or more interfaces was obtained.


Author(s):  
C.M. Teng ◽  
T.F. Kelly ◽  
J.P. Zhang ◽  
H.M. Lin ◽  
Y.W. Kim

Spherical submicron particles of materials produced by electrohydrodynamic (EHD) atomization have been used to study a variety of materials processes including nucleation of alternative crystallization phases in iron-nickel and nickel-chromium alloys, amorphous solidification in submicron droplets of pure metals, and quasi-crystal formation in nickel-chromium alloys. Some experiments on pure nickel, nickel oxide single crystals, the nickel/nickel(II) oxide interface, and grain boundaries in nickel monoxide have been performed by STEM. For these latter studies, HREM is the most direct approach to obtain particle crystal structures at the atomic level. Grain boundaries in nickel oxide have also been investigated by HREM. In this paper, we present preliminary results of HREM observations of NiO growth on submicron spheres of pure nickel.Small particles of pure nickel were prepared by EHD atomization. For the study of pure nickel, 0.5 mm diameter pure nickel wire (99.9975%) is sprayed directly in the EHD process. The liquid droplets solidify in free-flight through a vacuum chamber operated at about 10-7 torr.


10.1002/kin.7 ◽  
1996 ◽  
Vol 28 (9) ◽  
pp. 687-691 ◽  
Author(s):  
M. Calzadilla ◽  
A. Malpica ◽  
P. M. Diaz

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