Details

Autor(en) / Beteiligte

• Maricic, Aleksa
• Ristic, Momcilo

Titel

Corelation between the crystallisation process and change in thermoelectromotive force for the amorphous alloy Fe89.8Ni1.5Si5.2B3C0.5

Ist Teil von

• Science of sintering, 2003, Vol.35 (1), p.31-36

Ort / Verlag

International Institute for the Science of Sintering, Beograd

Erscheinungsjahr

2003

Link zum Volltext

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• Thermal and kinetic analyses of the structural changes for the amorphous alloy Fe89.8Ni1.5Si5.2B3C0.5, during the processes of non-isothermal heating and isothermal annealing, have been performed. The crystallisation process has been investigated using the method of differential scanning calorimetry (DSC). It is determined that this alloy crystalizes through three different stages. Changes in the electronic structure of the amorphous tape, for the temperature range 20 to 700?C have been studied. This was achieved by measuring the thermoelectromotive force (TEMS), of the thermo pair made of two tapes with same chemical structure of the alloy FeNiSiBC, but different atomic structure: one is in the crystal state (CL) and the other is in the amorphous state (AM). Analysis of the temperature dependence of the electromotive force has shown the following: the investigated alloy is thermically stable up to 450?C and changes in the atomic structure as well as equalising of the free electron density in both parts of the thermo pair AM-CL, take place in the temperature range from 450 to 550?C. Kinetic parameters of the process were determined by measuring time dependence of the TEMS in isothermic conditions at the temperatures 450, 480 and 510?C. Izvrsena su termicka i kineticka ispitivanja strukturnih promena tokom neizotermnog zagrevanja i izotermskog odgrevanja amorfne legure Fe89,8Ni1,5Si5,2B3C0,5. Metodom diferencijalne skanirajuce kalorimetrije (DSC) utvrdjeno je da ova legura kristalise u tri stupnja. Merenjem termoelektromotorne sile (TEMS), u toku zagrevanja termopara dobijenog spajanjem dve trake istog hemijskog sastava legure Fe89,8Ni1,5Si5,2B3C0,5, ali razlicite atomske strukture (jedna u kristalnom (CL), a druga u amorfnom stanju (AM)), utvrdjene su promene elektronske strukture amorfne trake u temperaturnom intervalu od 20 do 700?C. Analizom temperaturne zavisnosti elektromotorne sile pokazano je da je ispitivana legura termicki stabilna do 450?C, dok promena atomske strukture i izjednacavanje gustine slobodnih elektrona u oba dela termopara AM-SL nastaje u intervalu 450 do 550?C. Kineticki parametri procesa odredjeni su merenjem TEMS u zavisnosti od vremena u izotermskim uslovima na temperaturama od 450, 480 i 510?C.