Regensburg 1998 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

M: Metallphysik

M 22: Struktur und Umwandlungen II

M 22.2: Vortrag

Donnerstag, 26. März 1998, 10:30–10:50, H 39

Nucleation and growth versus spinodal decomposition in the Fe-Cr system — •S. M. Dubiel¹, J. Cieślak¹, B. Sepiol², and G. Vogl² — ¹Faculty of Physics and Nuclear Techniques, AGH University, PL-30-059 Kraków — ²Institut f. Materialphysik, Universität Wien, A-1090 Wien

Various quantities pertinent to ⁵⁷Fe Mössbauer effect (ME) were calculated assuming the decomposition in Fe−Cr alloys, resulting in the miscibility gap, occurs either via nucleation and growth or via spinodal process. Their comparison proves the ME is potentially able to distinguish between the two processes. The highest chance to make the distinction has been predicted to occur at middle stages of decomposition. ME measurements carried out in situ at elevated temperatures on a series of Fe−Cr alloys give evidence both modes of decomposition were active, depending on the alloy composition. The limit for the spinodal boundary can thus be determined precisely as well as the kinetics of decomposition. The results obtained will be presented and discussed.