The structure and mechanical properties of bulk Zr50Ti16.5Cu15Ni18.5 metall
ic glasses were studied by X-ray diffraction, scanning and transmission ele
ctron microscopy and by measurements of mechanical properties. The transiti
on from heterogeneous to homogeneous deformation was found to occur at 575
K. The crystallization was found to begin in the testing part of the sample
earlier than in the part placed in a holder during the mechanical testing.
The crystallization leads to the formation of the quasicrystalline phase w
ith a(0) = 2.54 Angstrom, hexagonal phase ZrTi(Ni,Cu) and hexagonal phase (
Zr6CoAl2 type). The difference of the structure in different parts of the s
ample has been observed and analyzed. The deformation does not effect on th
e crystallization processes occurring during the tensile testing at this te
mperature and the crystallization proceeds owing to the self-heating of the
samples during the phase transition. The correlation between mechanical pr
operties, structure and fracture surfaces is discussed. (C) 2001 Kluwer Aca
demic Publishers.