Effect of Cr addition on the glass-forming ability, magnetic properties, and corrosion resistance in FeMoGaPCBSi bulk glassy alloys

Abstract

The effect of Cr addition on the glass-forming ability ͑GFA͒, the magnetic properties, and corrosion resistance in Fe-Mo-GaP -C-B-Si glassy alloys was investigated. In addition to a slight increase of supercooled liquid region from 50 to 55 K, the substitution of a small amount of Fe with Cr was found to be effective for approaching alloy to a eutectic point, resulting in an increase in GFA. By copper mold casting, bulk glassy alloy rods with diameters up to 3 mm were produced. These glassy alloys exhibit a rather high saturation magnetization of 0.84-1.11 T with good soft-magnetic properties, i.e., low coercive force of 2.3-2.9 A / m, and high effective permeability of 13 360-15 960 at 1 kHz under a field of 1 A / m. The passive current density of the glassy alloy rod in 3 mass % NaCl solution decreased significantly from 1 ϫ 10 2 to 3 ϫ 10 −1 A/m 2 with an increase in Cr content, indicating that the addition of Cr is effective in enhancing the corrosion resistance.

Ductile Fe-Based Bulk Metallic Glass with Good Soft-Magnetic Properties

“…On the other hand, it has been suggested 19,20) that BMGs with low T g values are more likely to exhibit ductility. Compared with other iron-based BMGs, [1][2][3][4][5][8][9][10][11][12][13][14][15][16] the ductile Fe 75 Mo 5 -P 10 C 7:5 B 2:5 glassy alloy exhibited lower T g of 708 K, conformity with the correlation between ductility and T g to other ductile BMGs. and high DC permeability () of 47000.…”

“…[1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] Syntheses of iron-based metallic glasses with high glass-forming ability into a bulk form have further extended their potential applications as structural and functional materials. The first Fe-based bulk metallic glass (BMG) was reported in Fe-Al-Ga-P-C-B system in 1995, 3) subsequently a number of Fe-based BMGs have been developed, such as Fe-Ga-P-C-B-Si and Fe-B-based BMGs with good soft-magnetic properties, [4][5][6][7][8] Fe-Cr-Mo-C-B BMGs with high corrosion resistance, 9) amorphous steel alloys with high GFA and high strength of 3000-4000 MPa, [10][11][12] and Fe-Co-Nb-Si-B BMGs with extremely high strength of over 4000 MPa. 13) A ternary boron-rich Fe-Nb-B BMG with strength near 4 GPa was also recently reported.…”

Ductile Fe-Based BMGs with High Glass Forming Ability and High Strength

“…Chen et al 21,22) have pointed out that an s-d hybrid bonding could form by electrons transferring from the metalloid elements, such as P and B, to fill the d shells in the transition metal elements, such as Fe and Ni. The numbers of 3d band electrons in Fe is 6, while that of Ni is 8, so that the fraction of empty shell of 3d band will be reduced for the substitution of Ni for Fe in our alloys.…”

Syntheses and Fundamental Properties of Cr/Mo-Adoped Fe-Rich Alloys With Metastable Phase and Saturation Magnetization Near 1.9 T

“…It is expected to obtain the combination of such good properties by compositional modification. The study of Cr-adopted Fe-Si steel and Cr, Mo-adopted amorphous / glassy alloys indicate that the corrosion resistance can be improved by a small addition of Cr/Mo element [7][8][9] . On the contrary, however, the B s value decreases simultaneously 10,11 .…”