Skip to main content

Crystallization of Cobalt Amorphous Alloys Under Field Annealing

Buy Article:

$113.00 plus tax (Refund Policy)

Abstract:

Crystallization of Co-rich amorphous ribbons annealed under a 10 Oe external magnetic field at the early 30 minutes from their glassy status to supercooled liquid status is investigated by high-resolution transmission microscope (HR-TEM), Selected Area Fourier Transform (SA-FT), X-ray diffraction (XRD) and differential scanning calorimetry (DSC). Results indicate that the short-rang ordering feature can be refined very well in specimen annealed under temperatures about 87.4 °C below their glass transition (T g), showing refined salt-pepper morphologies with a mean length changing from 1.2±0.8 nm to 0.8±0.2 nm and a mean width shifting from 0.5±0.2 nm to 0.3±0.1 nm. When the amorphous ribbons are field-annealed at temperature near to T g (i.e., 450 °C), ultra-fine nanocrystalline structures can be formed on the top surface of ribbons with size of 3.5±0.5 nm and inter-grain spacing of about 0.4±0.2 nm even though the inner parts of the ribbons are still in amorphous phases. The nanocrystalline areas are featured by the formation of doped hcp cobalt phase orientated along the c-axis, with the inter-plane spacing ranging from 4 Å to 6 Å. When the annealing temperature is above T g, the grain sizes are increased dramatically with multi-phased nanocrystals precipitating from the amorphous substrate, and finally reaching almost complete crystallization at 600 °C, causing greatly coarsening of the nanocrystal structures.

Keywords: AMORPHOUS MATERIALS; COBALT; CRYSTALLIZATION; FIELD ANNEALING; NANOCRYSTALLINE MATERIALS

Document Type: Research Article

DOI: http://dx.doi.org/10.1166/jnn.2012.4262

Publication date: February 1, 2012

More about this publication?
  • Journal for Nanoscience and Nanotechnology (JNN) is an international and multidisciplinary peer-reviewed journal with a wide-ranging coverage, consolidating research activities in all areas of nanoscience and nanotechnology into a single and unique reference source. JNN is the first cross-disciplinary journal to publish original full research articles, rapid communications of important new scientific and technological findings, timely state-of-the-art reviews with author's photo and short biography, and current research news encompassing the fundamental and applied research in all disciplines of science, engineering and medicine.
  • Editorial Board
  • Information for Authors
  • Subscribe to this Title
  • Terms & Conditions
  • Ingenta Connect is not responsible for the content or availability of external websites
asp/jnn/2012/00000012/00000002/art00034
dcterms_title,dcterms_description,pub_keyword
6
5
20
40
5

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
X
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more