Iron-based bulk metallic glasses

Abstract

The current status of research and development in Fe-based bulk metallic glasses (BMGs) is reviewed. Bulk metallic glasses are relatively new materials possessing a glassy structure and large section thickness. These materials have an exciting combination of properties such as high mechanical strength, good thermal stability, large supercooled liquid region and potential for easy forming. Ever since the first synthesis of an Fe-based BMG in an Fe-Al-Ga-P-C-B system in 1995, there has been intense activity on the synthesis and characterisation of Fe-based BMGs. These BMGs exhibit some unique characteristics which have not been obtained in conventional Fe-based crystalline alloys. This uniqueness has led to practical uses of these bulk glassy alloys as soft magnetic and structural materials. This review presents the recent results on the glassforming ability, structure, thermal stability, mechanical properties, corrosion behaviour, soft magnetic properties and applications of Fe-based bulk glassy alloys developed during the last 15 years. This review also highlights the advanced analysis of their properties which has contributed significantly to the progress in understanding and developing of the Fe-based BMGs. The future prospects of Fe-based BMGs have also been presented.

Predictive modeling of glass forming ability in the Fe-Nb-B system using the CALPHAD approach

“…[4] Several similar indicators utilizing T g , T l , the solidification onset temperature (T s ) or crystallization temperature (T x ), e.g. T rg =T g /T s , T x =T x -T g , =T x /T l and =T x /(T g +T l ), [1] have later been proposed, suggesting that these values have at least some indicative power. While T g remains relatively stable, T l varies significantly with composition, and is therefore a powerful indicator during the design of new glassy alloys.…”

“…[1] Compared to standard electrical steel, which is commonly used for transformer cores, Febased metallic glasses show lower coercivity, higher permeability and resistivity, but somewhat lower saturation magnetization. Important factors hindering the widespread application of the amorphous alloys are, among others, their cost and the difficulty of designing or discovering new alloys.…”

Magnetic small-angle neutron scattering on bulk metallic glasses: A feasibility study for imaging displacement fields

“…Bulk metallic glasses (BMGs) are amorphous solids that are well known for their excellent mechanical properties, which render them attractive for many technological applications [1][2][3][4]. Although these materials are heavily investigated both experimentally and theoretically, the yielding and failure of BMGs under external strain are still not fully understood.…”

Kinetics and crystallization path of a Fe-based metallic glass alloy

“…Ln, Ga, Zr, Hf, Nb, Pd, Pr, Y) [12] limit the wide commercial acceptance of most alloy systems. The main market is still concentrated in Fe-based metallic glasses using abundant and inexpensive elements such as B, C, Si and P [13]. Their soft magnetic behavior and high saturation magnetization allow fabricating soft magnetic cores for high efficiency transformers, magnetic heads or electronic article surveillance items [9] that account for the most widespread applications.…”

“…High concentrations of Cr provide corrosion and oxidation resistance [28], while about 20 at.% of non-metals (C, B, P, S, N) are required to maintain the amorphous structure during cooling [13]. Subsequent property improvements are related to Mo, which reduces the intensity of the oxidizing effect required to ensure passivity and decreases the tendency of previously formed passive films to break down [29].…”