Dislocation Analysis of 4H-SiC Using KOH Low Temperature Etching

2014 ◽  
Vol 778-780 ◽  
pp. 358-361 ◽  
Author(s):  
Takahiro Sato ◽  
Yuya Suzuki ◽  
Hiroyuki Ito ◽  
Toshiyuki Isshiki ◽  
Munetoshi Fukui

The conventional KOH etching method at elevated temperatures is an easy way to study SiC dislocations, but presents problems due to an increased etch rate. Here, we examine the application of low temperature KOH treatment for the analysis of dislocation cores and etch pits in SiC. A low energy scanning electron microscope (SEM) is effective to classify dislocation kinds. The scanning transmission electron microscope (STEM) observation of thick samples prepared by the in situ micro-sampling technique enables evaluation of detailed dislocation properties.

2010 ◽  
Vol 16 (S2) ◽  
pp. 214-215
Author(s):  
T Tanigaki ◽  
K Ito ◽  
K Nakamura ◽  
Y Nagakubo ◽  
J Azuma ◽  
...  

Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010.


Author(s):  
Mihaela Albu ◽  
Bernd Panzirsch ◽  
Hartmuth Schröttner ◽  
Stefan Mitsche ◽  
Klaus Reichmann ◽  
...  

Powder and SLM additively manufactured parts of X5CrNiCuNb17-4 maraging steel were systematically investigated by electron microscopy to understand the relationship between the properties of the powder grains and the microstructure of the printed parts. We prove that satellites, irregularities and superficial oxidation of powder particles can be transformed into an advantage through the formation of nanoscale (AlMnSiTiCr)-oxides in the matrix during the printing process. The nano-oxides showed extensive stability in terms of size, spherical morphology, chemical composition and crystallographic disorder upon in situ heating up to 950°C in the scanning transmission electron microscope. Their presence thus indicates a potential for oxide-dispersive strengthening of this steel, which may be beneficial for creep resistance at elevated temperatures. The nucleation of copper clusters and their evolution into nanoparticles as well as the precipitation of Ni and Cr particles upon in situ heating have as well been systematically documented.


1995 ◽  
Vol 398 ◽  
Author(s):  
U. Herr ◽  
M. Poilack ◽  
D.L. Olynick ◽  
J.M. Gibson ◽  
R.S. Averback

ABSTRACTDisordered clusters of the intermetallic compounds Ni3Al and Cu3Au have been produced using a high pressure sputtering technique. The clusters are either embedded in a film or studied, in-situ in an UHV electron microscope. The evolution of the ordered structure upon annealing is studied. Using a scanning transmission electron microscope, electron diffraction is obtained from individual clusters. Partial ordering is observed in Cu3Au clusters which have been annealed below the bulk order-disorder transition temperature. Under the experimental conditions, only clusters with sizes of 10–15 nm or larger show ordering.


Materials ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 7784
Author(s):  
Mihaela Albu ◽  
Bernd Panzirsch ◽  
Hartmuth Schröttner ◽  
Stefan Mitsche ◽  
Klaus Reichmann ◽  
...  

Powder and selective laser melting (SLM) additively manufactured parts of X5CrNiCuNb17-4 maraging steel were systematically investigated by electron microscopy to understand the relationship between the properties of the powder grains and the microstructure of the printed parts. We prove that satellites, irregularities and superficial oxidation of powder particles can be transformed into an advantage through the formation of nanoscale (AlMnSiTiCr) oxides in the matrix during the printing process. The nano-oxides showed extensive stability in terms of size, spherical morphology, chemical composition and crystallographic disorder upon in situ heating in the scanning transmission electron microscope up to 950 °C. Their presence thus indicates a potential for oxide-dispersive strengthening of this steel, which may be beneficial for creep resistance at elevated temperatures. The nucleation of copper clusters and their evolution into nanoparticles, and the precipitation of Ni and Cr particles upon in situ heating, have been systematically documented as well.


2014 ◽  
Vol 20 (2) ◽  
pp. 323-329 ◽  
Author(s):  
Nestor J. Zaluzec ◽  
M. Grace Burke ◽  
Sarah J. Haigh ◽  
Matthew A. Kulzick

AbstractThe use of analytical spectroscopies during scanning/transmission electron microscope (S/TEM) investigations of micro- and nano-scale structures has become a routine technique in the arsenal of tools available to today’s materials researchers. Essential to implementation and successful application of spectroscopy to characterization is the integration of numerous technologies, which include electron optics, specimen holders, and associated detectors. While this combination has been achieved in many instrument configurations, the integration of X-ray energy-dispersive spectroscopy and in situ liquid environmental cells in the S/TEM has to date been elusive. In this work we present the successful incorporation/modifications to a system that achieves this functionality for analytical electron microscopy.


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