The kinetics of amorphous-nanocrystalline transformation for a finemet alloy

Research output: Contribution to journalArticle

25 Citations (Scopus)

Abstract

The kinetics of the nanocrystalline structure formation from its amorphous precursor was investigated for a Finemet alloy with the composition Fe73.5Nb3Cu1Si13.5B 9. The time- and temperature-dependent transformation was followed in parallel by differential scanning calorimetry (DSC), thermoelectric power (TEP) and Vickers microhardness (HV) measurements on ribbon samples 10 mm wide. After annealing the samples in a tin bath at 500, 525, 550 and 575 °C for different annealing times between 5 s and 2 h, the TEP and HV data were measured at room temperature. Using the conventional Johnson-Mehl-Avrami method, for the apparent activation energy we deduced values from 3.58 to 3.93 eV from the TEP data and values from 3.84 to 4.08 eV from the HV data which agree well with the value we obtained from DSC measurements using the Kissinger method (4.1 ± 0.4 eV). Our DSC measurements on partially crystallized samples revealed a third intermediate exothermal peak beside the well-known two peaks. This was attributed to the segregation of a silicide compound out of the α-Fe(Si) solid solution.

Original languageEnglish
Pages (from-to)567-571
Number of pages5
JournalMaterials Science and Engineering A
Volume179-180
Issue numberPART 1
DOIs
Publication statusPublished - May 1 1994

    Fingerprint

ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

Cite this