FeCoBSiNb bulk metallic glasses with Cu additions

Abstract

The effect of Cu additions (1, 2 and 3 at.%) on the glass forming ability (GFA) and magnetic properties of [(Fe0.5Co0.5)0.75Si0.05B0.20]96Nb4 is studied. As the Cu content increases, the GFA deteriorates. The structure of the samples, as well as the crystallization behavior was in‐situ studied by means of synchrotron beam. The as‐cast 1 mm diameter rods are characterized by a mixture of (nano)‐crystals and amorphous matrix. Upon heating, the pre‐existing nuclei grow, without forming new crystalline phases. The magnetic properties are characteristic for soft magnetic materials. Despite that several crystalline magnetic phases can be identified in the as‐cast samples, only one single magnetic transition prior to complete crystallization could be identified upon heating. The values for saturation magnetization and for Curie temperature are relatively close for all samples. The initial permeability of the Cu containing samples seems to be higher than that for the fully amorphous [(Fe0.5Co0.5)0.75Si0.05B0.20]96Nb4 alloy (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Enhancing glass-forming ability via frustration of nano-clustering in alloys with a high solvent content

“…It was argued that copper additions can stimulate nucleation of α-Fe and effectively refine the α-Fe grain sizes to 20 nm or below. Although these Cu-containing Fe-based metallic glasses have a large saturation magnetization close to that of the conventional Fe-Si alloys, their GFA is reduced and the maximum attainable size is limited to the micrometer level1415161718192021, which is consistent with the results in the Fe-Co-based alloys222324. In our study, however, we surprisingly found that minor doping of the element Cu is actually very effective in destabilizing the α-Fe nano-clusters and promoting the GFA.…”

Electrochemical and biological characterization of Ti–Nb–Zr–Si alloy for orthopedic applications

“…Other studies showed that a ternary Ti-Nb-Zr alloy has improved stability of the surface films exhibiting exceptionally high resistance to oxidizing acids 39,43 . Some reports showed the role of Si in the stabilizing the crystallized phases in Si-Nb-based alloys that might be helpful to promote corrosion resistance [67][68][69][70] . It has been also reported that the addition of Si can improve the corrosion resistance of Ti alloys in acidic solutions due to the formation of stable SiO2 and Si-doped TiO2 passive layers on the Ti-Si alloy 34,71 .…”

FeSiBPNbCu Bulk Nanocrystalline Alloys with High GFA and Excellent Soft-Magnetic Properties

“…However, the H c increased rapidly and the B s began to decrease upon the emergence of Fe 3 (B,P), resulting from annealing at T a of 783 K or higher. Table 1 lists the GFA (D cr ) and Magnetic Properties (H c , B s , and µ e ) of the alloys developed in this work and some other Fe-based bulk nanocrystalline alloys widely reported previously [1,9,13]. The developed FeSiBPNbCu bulk nanocrystalline alloys with minor Nb addition show comprehensively excellent properties, especially for the combination of high GFA and high B s , namely, D cr of 1-2.5 mm and high B s of 1.42-1.5 T, but also low H c of 0.86-2 A/m, high µ e at 1 kHz of 15,000-18,500.…”

“…Some attempts have been made to synthesize Fe-based bulk nanocrystalline alloys with high GFA and SMPs. Resultantly, a series of alloys have been successfully developed [12][13][14][15][16][17][18], which can be made into thick ribbons or nanocrystalline rod-shaped samples. Recently, by logically adding Cu, FeSiBPNbCu alloys with high GFA and SMPs were successfully developed by our team [18].…”