A TEM study of transient oxide scales on β-NiAl

1984 ◽  
Vol 42 ◽  
pp. 598-599
Author(s):  
J. Doychak
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Single Crystal ◽  
Metal Substrate ◽  
Oxide Scales ◽  
Orientation Relationships ◽  
Epitaxial Relationship ◽  
Transient Oxidation ◽  
Transmission Electron ◽  
Oxide Phases

The oxidation sequence of alumina forming alloys usually involves a period when transient, metastable phases of Al2O3 form rather than the thermoydnamically stable α-Al2O3 phase. The structures of these phases are spinel derivatives and are found to have a strong epitaxial relationship to the metal substrate. Using single-crystal β-NiAl doped with 0.1 wt.%Zr, the oxide phases that form in air at 800°C and the orientation relationships that exist between the oxides and metal substrate were determined using transmission electron microscopy. Once the transient oxidation stages are characterized, an understanding of the formation of stable α-Al2O3 scales can be more easily obtained.

Epitaxy of Nb3 Sn Films on Sapphire

1984 ◽  
Vol 37 ◽  
Author(s):  
A. F. Marshall ◽  
F. Hellman ◽  
B. Oh
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Film Thickness ◽  
Single Crystal ◽  
Domain Structure ◽  
High Temperatures ◽  
Defect Structure ◽  
Epitaxial Relationship ◽  
Crystal Matrix ◽  
Transmission Electron

AbstractFilms of Nb3Sn vapor deposited at low rates and high temperatures on (1102) sapphire form an epitaxial <100> single crystal matrix with a domain structure of misoriented regions bounded by low-angle dislocation boundaries. Nucleation of other orientations at the interface result in a highly oriented but polycrystalline film through approximately the first thousand Angstroms of film thickness. After this point random orientations become overgrown by epitaxial <100> regions. At slightly lower temperatures many small <100> grains with a second epitaxial relationship also nucleate at the interface. These rotated grains persist through greater thicknesses than random orientations. The misorientation defect structure of the single crystal matrix is analyzed by transmission electron microscopy.

Orientation Relationships between BCC Deposits and FCC Substrates

1987 ◽  
Vol 94 ◽  
Author(s):  
David A. Smith ◽  
Armin Segmüller ◽  
A. R. Taranko
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Single Crystal ◽  
Grazing Incidence ◽  
X Ray Diffraction ◽  
Orientation Relationships ◽  
X Ray ◽  
Bcc Metals ◽  
Transmission Electron ◽  
Deposited Films

ABSTRACTOriented deposits are commonplace in vapor deposited films. The origins of this behavior are not always clear. Various bcc metals (Fe, Nb, Mo, Ta, Cr) have been deposited onto single crystal fcc substrates (Au, Ni, MgO, Si, NaCI) which were selected with the intention of varying the character of the substrate-deposit interaction. The resulting structures have been characterized by transmission electron microscopy and grazing incidence x-ray diffraction. The observed variants of the cube-cube and Nishiyama-Wassermann orientation relationship can be understood in terms of minimization of misfit except when there is a weak interaction between substrate and deposit.

Transmission Electron Microscopy studies of texture of Cr underlayer of magnetic recording hard disk

1991 ◽  
Vol 49 ◽  
pp. 580-581
Author(s):  
L. Tang ◽  
G. Thomas ◽  
M. R. Khan ◽  
S. L. Duan
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Magnetic Recording ◽  
Magnetic Thin Films ◽  
Magnetic Films ◽  
Substrate Bias ◽  
Epitaxial Relationship ◽  
Transmission Electron

Cr thin films are often used as underlayers for Co alloy magnetic thin films, such as Co1, CoNi2, and CoNiCr3, for high density longitudinal magnetic recording. It is belived that the role of the Cr underlayer is to control the growth and texture of the Co alloy magnetic thin films, and, then, to increase the in plane coercivity of the films. Although many epitaxial relationship between the Cr underlayer and the magnetic films, such as ﹛1010﹜Co/ {110﹜Cr4, ﹛2110﹜Co/ ﹛001﹜Cr5, ﹛0002﹜Co/﹛110﹜Cr6, have been suggested and appear to be related to the Cr thickness, the texture of the Cr underlayer itself is still not understood very well. In this study, the texture of a 2000 Å thick Cr underlayer on Nip/Al substrate for thin films of (Co75Ni25)1-xTix dc-sputtered with - 200 V substrate bias is investigated by electron microscopy.

scholarly journals Transmission electron microscopy analysis of the crystallography of precipitates in Mg–Sn alloys aged at high temperatures

2014 ◽  
Vol 47 (5) ◽  
pp. 1729-1735 ◽  
Author(s):  
Xin Nie ◽  
Yimin Guan ◽  
Dongshan Zhao ◽  
Yu Liu ◽  
Jianian Gui ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Three Dimensional ◽  
Dark Field ◽  
Peak Hardness ◽  
Invariant Line ◽  
Orientation Relationships ◽  
Transmission Electron Microscopy Analysis ◽  
Transmission Electron ◽  
Annular Dark Field

The crystallographic orientation relationships (ORs) of precipitated β-Mg2Sn particles in Mg–9.76 wt% Sn alloy aged at 573 K for 5 h, corresponding to its peak hardness, were investigated by advanced transmission electron microscopy (TEM). OR-3 of (110)β//(0001)αand [\overline 111]β//[1\overline 210]αand OR-4 of (110)β//(0001)αand [001]β//[2\overline 1\overline 10]αare the key ORs of β-Mg2Sn particles in the alloy. The proportions of β-Mg2Sn particles exhibiting OR-3 and OR-4 were determined as 75.1 and 24.3%, respectively. Crystallographic factors determined the predominance of OR-3 in the precipitated β-Mg2Sn particles. This mechanism was analyzed by a three-dimensional invariant line model constructed using a transformation matrix in reciprocal space. Models of the interface of precipitated β-Mg2Sn and the α-Mg matrix were constructedviahigh-resolution TEM and atomic resolution high-angle annular dark-field scanning TEM.

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