The static and dynamic mechanical properties of metallic glass wires of compositions Fe85-x-yCrxSiyB15 (x = 0-8, y = 7.5) or 10) have been investigated. A modified design of bending fatigue machine was employed for the dynamic tests. The static strength of the as-cast metallic glass wire (σf = 3000-3800 MPa and Hv = 900-1080) increased relatively slowly on substitution of Fe by up to 10 at.% Cr. The fatigue strength was, however, strongly dependent on Cr content. This indicated that Cr substitution for Fe was effective in enhancing the fatigue strength of FeSiB at lower concentration than has previously been reported. X-ray photoelectron spectroscopy observations suggest that the Cr-induced fatigue strength enhancement is due mainly to the presence of an oxide film rich in Si and Cr (oxides) on the surface of the wire.
Relation
Materials Science and Engineering: A / Vol. 186, No. 1-2, pp.143-149