STATISTICAL INVESTIGATIONS OF FRACTURE DEMONSTRATIONS ON NI-SI-B METALLIC-GLASS RIBBONS FAILED IN TENSION AT 4.2 TO 300-K

It is known that the failure of amorphous metallic materials under uniaxial tensile stress at temperatures much lower than the glass transition temperature is preceded by an intense shear deformation localized into narrow bands. However, the real fracture surface is more complicated and is not formed by a single shear band. The aim of our work was to suggest a possible clarification of this phenomenon. We measured the dependence of the lengths of the sections in which the crack propagated in one of the two possible planes, on temperature. For measurements we used samples of Ni//8//0Si//1//0B//1//0 and Ni//8//0Si//5B//1//5 amorphous ribbons. Experimental results lead us to suppose that high external mechanical stressing acting for a sufficiently long time may influence the polarization and thus lengthen the sections of the fracture surface in which the crack propagates in a single shear plane.