Design and investigation of an FeSiBCNb metallic glass with low electrical and thermal conductivity

In this work, a cost-efficient Fe-based metallic glass in the Fe74BxSiyCzNb2 (x + y + z = 24) composition range with low electrical and thermal conductivity is developed. Ingots with different alloy compositions are produced from high-purity Fe, B, Si, C, Nb powders in a tube furnace and processed into metallic ribbons by melt spinning. The high content of various metalloids in the compositions is expected to enhance the electrical resistivity and lower the thermal conductivity in the amorphous phase. The thermophysical properties and the amorphous structure of the ribbon samples are investigated by x-ray diffractometry (XRD), differential scanning calorimetry (DSC), dilatometry (DSD) and high resolution transmission electron microscopy (HRTEM). The investigations confirm that the characteristic temperatures Tg, Tm, Tx and Tl of the alloy and thus its GFA are strongly dependent on the atomic composition. A particularly good glass forming ability (GFA) is achieved with the alloy composition Fe74B8Si12C4Nb2. In addition to that a high hardness of 984 HV0.1 and a thermal conductivity as low as 6.41 W/mK is observed. It is concluded that metallic glasses in the Fe74BxSiyCzNb2 (x + y + z = 24) composition range can be considered as a cost-effective coating material for thermal insulation in a temperature range below Tg approximate to 540 degrees C, as well as electrical components and wear protection. (c) 2022 Elsevier B.V. All rights reserved.

Automated summary

In this study, a cost-efficient Fe-based metallic glass with low electrical and thermal conductivity is developed and its thermophysical properties and amorphous structure are investigated. The results indicate that the alloy with a specific composition of Fe74B8Si12C4Nb2 has excellent glass forming ability and high hardness.