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Structural and Morphological Changes of Co Nanoparticles and Au-10at.%Pd Thin Film Studied by in Situ Heating in a Transmission Electron Microscope

  • Ji, Yoon-Beom (Research & Development, Sung-Il Turbine Co., Ltd.) ;
  • Park, Hyun Soon (Department of Materials Science and Engineering, Inha University)
  • Received : 2017.08.22
  • Accepted : 2017.09.06
  • Published : 2017.09.30

Abstract

The microstructural changes in Co nanoparticles and an Au-10at.%Pd thin film have been investigated using an in situ heating holder with a micro-electro-mechanical system (MEMS). In Co nanoparticles, two phases (face-centered cubic and hexagonal close-packed crystal structures) were found to coexist at room temperature and microstructures at temperatures, higher than $1,000^{\circ}C$, were observed with a quick response time and significant stability. The actual temperature of each specimen was directly estimated from the changes in the lattice spacing (Bragg-peak separation). For the Au-10at.%Pd thin film, at a set temperature of $680^{\circ}C$, the actual temperature of the sample was estimated to be $1,020^{\circ}C{\pm}123^{\circ}C$. Note that the specimen temperature should be carefully evaluated because of the undesired effects, i.e., the temperature non-uniformity due to the sample design of the MEMS chip, and distortion due to thermal expansion.

Keywords

References

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