Effect of Ni-substitution on glass forming ability, mechanical, and magnetic properties of FeBNbY bulk metallic glasses

Abstract

We present a method to identify bulk glass forming ability by partial substitution of Fe by Ni in FeBNbY based amorphous alloy ribbons and as a consequence obtain enhanced mechanical and soft magnetic properties of bulk glassy rods of diameter as large as 4.5 mm. A detailed investigation of thermal, mechanical, and magnetic properties of (Fe0.72−x NixB0.24Nb0.04)95.5Y4.5 alloys (with x ∼ 0.02, 0.04, 0.06, 0.08, 0.1) was carried out. The supercooled regime (ΔTx) and other glass forming parameters, e.g., reduced glass transition temperature (Trg), the gamma (γ) parameter, etc., were found to be enhanced due to the Ni substitution resulting in improvement of glass forming ability (GFA). The maximum values of such parameters (ΔTx ∼ 94 K, Trg ∼ 0.644, and γ ∼ 0.435) were obtained for the alloy with x ∼ 0.06, making it possible to cast cylindrical rods with 4.5 mm diameter for this composition. Nanoindentation studies on glassy rods also point out that (Fe0.66Ni0.06B0.24Nb0.04)95.5Y4.5 alloy exhibit the maximum value of hardness (H ∼ 12 GPa) as well as elastic modulus (E ∼ 193 GPa) among all of these samples. In addition to these, that particular sample shows the lowest room temperature coercivity (Hc ∼ 210 mOe). By annealing at 823 K, Hc can be further reduced to 60 mOe due to its structural relaxation. We attribute the improved soft magnetic and mechanical properties of as-quenched (Fe0.66Ni0.06B0.24Nb0.04)95.5Y4.5 alloy to higher packing density attained due to its large glass forming ability.

Synthesis of CoCrMoCB bulk metallic glasses with high strength and good plasticity via regulating the metalloid content

“…Because of different electron configurations and various atomic radii among metalloid atoms (B, C, Si, P) and metal atoms, the contents of metalloid elements and metal elements could change the atomic bonding character and the degree of dense randomly packed atomic configuration [13][14][15][16][17][18]. In light of this, the contents of metalloid elements could play an important role in determining the GFA and macroscopic mechanical properties [4,13,14,17,19].…”

“…The atomic bonding character between metalmetalloid atoms is more covalent-like [2,10]. This has a strong influence on the activation energy barrier of the fundamental flow units or the global bonding strength [11,12], and additionally, affects the GFA and macroscopic mechanical properties of BMGs [13][14][15][16][17]. On the other hand, both the GFA and mechanical properties are also influenced by the degree of dense randomly packed atomic configuration [4,[16][17][18].…”

Fabrication and tuning soft magnetic and magneto-optical properties of BMGs based Fe-B-Nb-Ni transparent thin films, obtained by Pulsed Laser Deposition.

“…Bulk metallic glasses, BMGs, are of great importance owing unique disorder structure, exceptional mechanical strength, high corrosion resistance and excellent soft-magnetic properties [7]. Among these new class of materials Iron (Fe) based BMGs have been widely investigated for their excellent soft-magnetism [7].…”

“…Among these new class of materials Iron (Fe) based BMGs have been widely investigated for their excellent soft-magnetism [7]. Although the metallic glasses in their bulk form are widely investigated, studies on the thin films of this new class of materials retaining their excellent properties are rather a recent area of developments.…”

Structure, Core Losses, Curie Temperature, Defects in the Structure of the Bulk Amorphous Alloy Fe55Co15W2Y8B20

“…In the production of bulk amorphous alloys, the formation of appropriate shapes is very difficult due to their high brittleness [24,25]. The bulk amorphous iron-based materials have a great brittleness [26][27][28][29].This separated group of alloys with the appropriate chemical composition may exhibit magnetic properties, so-called soft or hard [30,31]. When it comes to hard magnetic materials, it is difficult to talk about the amorphous structure and the good properties of the so-called hard.…”