Surface crystallization of amorphous Fe-=SUB=-73.8-=/SUB=-Si-=SUB=-13-=/SUB=-B-=SUB=-9.1-=/SUB=-Cu-=SUB=-1-=/SUB=-Nb-=SUB=-3.1-=/SUB=- and Fe-=SUB=-77.5-=/SUB=-Si-=SUB=-13.5-=/SUB=-B-=SUB=-9-=/SUB=- microwires

Amorphous microwires of Fe73.8Si13B9.1Cu1Nb3.1 andFe77.5Si13.5B9 composition fabricated by the Ulitovsky--Taylor method were studied. The samples with the glass shell removed were heated at temperatures of 753 K and 703 K for 20 min, afterwards, their structure was examined using X-ray diffraction. Subsequently, the thermally treated samples were chemically etched and X-ray diffraction study of the structure was again carried out. Experimental results on the predominant crystallization of near-surface regions were discussed assuming that mechanical stresses affect the nucleation and growth of nanocrystals. Keywords: amorphous materials, stress distribution, nanocrystallization, X-ray diffraction.