Analyses of Phase Transformation Mechanism Based on In Situ Observation during Ti-10Nb-5Sn Alloy Heating Cycles

The Ti-10Nb-5Sn alloy was heated and cooled repeatedly in a heater system located in transmission electron microscope chamber. The phase and morphology transformation was in situ observed to analyze the transformation mechanism from austenite β to martensite phase. The results reveal that he Ti-10Nb-5Sn alloy has round trip shape memory function.

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Nanosecond in situ transmission electron microscope studies of the reversible Ge2Sb2Te5 crystalline ⇔ amorphous phase transformation

Journal of Applied Physics ◽

10.1063/1.3678447 ◽

2012 ◽

Vol 111 (2) ◽

pp. 024309 ◽

Cited By ~ 22

Author(s):

M. K. Santala ◽

B. W. Reed ◽

T. Topuria ◽

S. Raoux ◽

S. Meister ◽

...

Keyword(s):

Phase Transformation ◽

Electron Microscope ◽

Amorphous Phase ◽

Transmission Electron Microscope ◽

Transmission Electron

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The L12 to DO19 Phase Transformation In The Intermetallic Compound Fe3Ge

MRS Proceedings ◽

10.1557/proc-481-225 ◽

1997 ◽

Vol 481 ◽

Author(s):

Q. Z. Chen ◽

A. H. W. Ngan ◽

B. J. Duggan

Keyword(s):

Phase Transformation ◽

Electron Microscope ◽

Intermetallic Compound ◽

Transmission Electron Microscope ◽

Stacking Fault ◽

Transmission Electron ◽

Do19 Phase ◽

Annealing Experiments

ABSTRACTA large kinetics hysteresis is found to exist between the forward and backward reactions of the L12 ↔ DO19 transformation in Fe3Ge. The slow DO19 to L12 transformation leaves behind very stable twins and stacking fault debris. In-situ annealing experiments in the transmission electron microscope revealed that nucleation for the reverse L12 to DO19 reaction takes place efficiently at these defects.

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In Situ Observation of Electron Beam-Induced Phase Transformation of CaCO3 to CaO via ELNES at Low Electron Beam Energies

Microscopy and Microanalysis ◽

10.1017/s1431927614000464 ◽

2014 ◽

Vol 20 (3) ◽

pp. 715-722 ◽

Cited By ~ 14

Author(s):

Ute Golla-Schindler ◽

Gerd Benner ◽

Alexander Orchowski ◽

Ute Kaiser

Keyword(s):

Phase Transformation ◽

Electron Beam ◽

Electron Microscope ◽

Bond Length ◽

Transmission Electron Microscope ◽

Low Voltage ◽

In Situ Observation ◽

Edge Structure ◽

Transmission Electron

AbstractIt is demonstrated that energy-filtered transmission electron microscope enables following of in situ changes of the Ca-L2,3 edge which can originate from variations in both local symmetry and bond lengths. Low accelerating voltages of 20 and 40 kV slow down radiation damage effects and enable study of the start and finish of phase transformations. We observed electron beam-induced phase transformation of single crystalline calcite (CaCO3) to polycrystalline calcium oxide (CaO) which occurs in different stages. The coordination of Ca in calcite is close to an octahedral one streched along the <111> direction. Changes during phase transformation to an octahedral coordination of Ca in CaO go along with a bond length increase by 5 pm, where oxygen is preserved as a binding partner. Electron loss near-edge structure of the Ca-L2,3 edge show four separated peaks, which all shift toward lower energies during phase transformation at the same time the energy level splitting increases. We suggest that these changes can be mainly addressed to the change of the bond length on the order of picometers. An important pre-condition for such studies is stability of the energy drift in the range of meV over at least 1 h, which is achieved with the sub-Ångström low-voltage transmission electron microscope I prototype microscope.

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Remote On-Line Control of a High-Voltage in situ Transmission Electron Microscope with A Rational User Interface

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100164386 ◽

1996 ◽

Vol 54 ◽

pp. 384-385

Author(s):

M.A. O’Keefe ◽

J. Taylor ◽

D. Owen ◽

B. Crowley ◽

K.H. Westmacott ◽

...

Keyword(s):

Electron Microscopy ◽

Electron Microscope ◽

User Interface ◽

Transmission Electron Microscope ◽

High Voltage ◽

Materials Science ◽

Transmission Electron ◽

On Line ◽

Electron Microscopes

Remote on-line electron microscopy is rapidly becoming more available as improvements continue to be developed in the software and hardware of interfaces and networks. Scanning electron microscopes have been driven remotely across both wide and local area networks. Initial implementations with transmission electron microscopes have targeted unique facilities like an advanced analytical electron microscope, a biological 3-D IVEM and a HVEM capable of in situ materials science applications. As implementations of on-line transmission electron microscopy become more widespread, it is essential that suitable standards be developed and followed. Two such standards have been proposed for a high-level protocol language for on-line access, and we have proposed a rational graphical user interface. The user interface we present here is based on experience gained with a full-function materials science application providing users of the National Center for Electron Microscopy with remote on-line access to a 1.5MeV Kratos EM-1500 in situ high-voltage transmission electron microscope via existing wide area networks. We have developed and implemented, and are continuing to refine, a set of tools, protocols, and interfaces to run the Kratos EM-1500 on-line for collaborative research. Computer tools for capturing and manipulating real-time video signals are integrated into a standardized user interface that may be used for remote access to any transmission electron microscope equipped with a suitable control computer.

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