SMA and SME in Cu-Zn-Al Alloys: Local Studies in α, ε, T Space

1991 ◽  
Vol 246 ◽  
Author(s):  
A. Amengual ◽  
A. Isalgué ◽  
F.C. Lovey ◽  
F. Marco ◽  
V. Torra
Keyword(s):  
High Resolution ◽  
Mechanical Stress ◽  
Single Crystals ◽  
Experimental Observation ◽  
Hysteresis Loops ◽  
Al Alloys ◽  
Material Behaviour ◽  
Electronic Concentration ◽  
The Creation

AbstractThe use of Cu-Zn-Al single crystals (electronic concentration e/a= 1.48) and of a high resolution equipment allows to study the evolution of one or few martensite domains. This kind of study proves the existence of intrinsic thermoelasticity, the differences between different friction processes (interface movements and nucleation) and also the coherence of the hysteresis loops obtained through mechanical stress or temperature. The different evolutions linked to the creation of dislocations or to the change of é precipitates can clearly be seen during the cycling. The observations allow to establish a model of the material behaviour consistent with experimental observation.

Compression-Induced Martensitic Transformations in Cu-Zn-Al Alloys with e/a > 1.50

1996 ◽  
Vol 459 ◽  
Author(s):  
A. Cuniberti ◽  
R. Romero
Keyword(s):  
Single Crystals ◽  
Martensitic Transformations ◽  
Al Alloys ◽  
Tension Test ◽  
Stress Strain ◽  
Different Temperatures ◽  
Electronic Concentration

ABSTRACTResults are reported about the pseudoelastic cycles β-martensite obtained by compression of β Cu-Zn-Al single crystals with electronic concentration 1.52. Stress-strain curves at different temperatures and in situ observations were carried out. The results are compared with those obtained from tension test.

Imaging of polymer single crystals in low-voltage, high-resolution scanning electron microscopy

1990 ◽  
Vol 48 (4) ◽  
pp. 1106-1107
Author(s):  
W.W. Adams ◽  
G. Price ◽  
A. Krause
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
High Resolution ◽  
Single Crystals ◽  
Low Voltage ◽  
Polymer Surface ◽  
Beam Current ◽  
Image Features ◽  
First Results ◽  
Scanning Electron

It has been shown that there are numerous advantages in imaging both coated and uncoated polymers in scanning electron microscopy (SEM) at low voltages (LV) from 0.5 to 2.0 keV compared to imaging at conventional voltages of 10 to 20 keV. The disadvantages of LVSEM of degraded resolution and decreased beam current have been overcome with the new generation of field emission gun SEMs. In imaging metal coated polymers in LVSEM beam damage is reduced, contrast is improved, and charging from irregularly shaped features (which may be unevenly coated) is reduced or eliminated. Imaging uncoated polymers in LVSEM allows direct observation of the surface with little or no charging and with no alterations of surface features from the metal coating process required for higher voltage imaging. This is particularly important for high resolution (HR) studies of polymers where it is desired to image features 1 to 10 nm in size. Metal sputter coating techniques produce a 10 - 20 nm film that has its own texture which can obscure topographical features of the original polymer surface. In examining thin, uncoated insulating samples on a conducting substrate at low voltages the effect of sample-beam interactions on image formation and resolution will differ significantly from the effect at higher accelerating voltages. We discuss here sample-beam interactions in single crystals on conducting substrates at low voltages and also present the first results on HRSEM of single crystal morphologies which show some of these effects.

scholarly journals Tunable magnetization steps in mixed valent ferromagnet Eu2CoMnO6

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Nara Lee ◽  
Jong Hyuk Kim ◽  
Dong Gun Oh ◽  
Hyun Jun Shin ◽  
Hwan Young Choi ◽  
...  
Keyword(s):  
Material Processing ◽  
Magnetic Properties ◽  
Single Crystals ◽  
Magnetic State ◽  
Hysteresis Loops ◽  
Double Perovskite ◽  
Processing Parameters ◽  
Perovskite Oxides ◽  
Efficient Approach ◽  
Isothermal Magnetization

AbstractMagnetic properties can be manipulated to enhance certain functionalities by tuning different material processing parameters. Here, we present the controllable magnetization steps of hysteresis loops in double-perovskite single crystals of Eu2CoMnO6. Ferromagnetic order emerges below TC ≈ 122 K along the crystallographic c axis. The difficulty in altering Co2+ and Mn4+ ions naturally induces additional antiferromagnetic clusters in this system. Annealing the crystals in different gas environments modifies the mixed magnetic state, and results in the retardation (after O2-annealing) and bifurcation (after Ar-annealing) of the magnetization steps of isothermal magnetization. This remarkable variation offers an efficient approach for improving the magnetic properties of double-perovskite oxides.

High resolution 14N NMR in solids: Single crystals of ammonium hydrogen oxalate hemihydrate

1977 ◽  
Vol 66 (12) ◽  
pp. 5433-5438 ◽  
Author(s):  
E. K. Wolff ◽  
R. G. Griffin ◽  
C. Watson
Keyword(s):  
High Resolution ◽  
Single Crystals ◽  
Ammonium Hydrogen ◽  
14N Nmr

X-ray topo-tomography studies of linear dislocations in silicon single crystals

2018 ◽  
Vol 51 (6) ◽  
pp. 1616-1622 ◽  
Author(s):  
Victor Asadchikov ◽  
Alexey Buzmakov ◽  
Felix Chukhovskii ◽  
Irina Dyachkova ◽  
Denis Zolotov ◽  
...  
Keyword(s):  
Numerical Analysis ◽  
High Resolution ◽  
Single Crystals ◽  
Complete Characterization ◽  
Reconstruction Technique ◽  
Algebraic Reconstruction Technique ◽  
X Ray ◽  
Laboratory Setup ◽  
Simultaneous Algebraic Reconstruction Technique

This article describes complete characterization of the polygonal dislocation half-loops (PDHLs) introduced by scratching and subsequent bending of an Si(111) crystal. The study is based on the X-ray topo-tomography technique using both a conventional laboratory setup and the high-resolution X-ray image-detecting systems at the synchrotron facilities at KIT (Germany) and ESRF (France). Numerical analysis of PDHL images is performed using the Takagi–Taupin equations and the simultaneous algebraic reconstruction technique (SART) tomographic algorithm.

High resolution triple resonance micro magic angle spinning NMR spectroscopy of nanoliter sample volumes

2016 ◽  
Vol 18 (6) ◽  
pp. 4902-4910 ◽  
Author(s):  
J. Ole Brauckmann ◽  
J. W. G. (Hans) Janssen ◽  
Arno P. M. Kentgens
Keyword(s):  
Solid State ◽  
Nmr Spectroscopy ◽  
High Resolution ◽  
Single Crystals ◽  
Solid State Nmr ◽  
Magic Angle Spinning ◽  
Magic Angle ◽  
Triple Resonance ◽  
Angle Spinning

To be able to study mass-limited samples and small single crystals, a triple resonance micro-magic angle spinning (μMAS) probehead for the application of high-resolution solid-state NMR of nanoliter samples was developed.

Direct imaging of direction-controlled molecular rotational wave packets created by a polarization-skewed double-pulse

2020 ◽  
Vol 22 (19) ◽  
pp. 10853-10862
Author(s):  
Kenta Mizuse ◽  
Naoya Sakamoto ◽  
Romu Fujimoto ◽  
Yasuhiro Ohshima
Keyword(s):  
High Resolution ◽  
Wave Packets ◽  
Double Pulse ◽  
Direct Imaging ◽  
Creation Process ◽  
Rotational Wave ◽  
The Creation

High-resolution molecular movies of direction-controlled rotational wave packets are reported, providing insights into the creation process and detailed dynamics of wave packets.

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