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Abstract The effects of metalloid admixture on the amorphous forming ability (AFA) of the Fe 100-4 x P x B x C x Si x (x = 7, 8, 9, 10) alloy powders, which are prepared by mechanical alloying technology, are investigated by means of X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The results show that the AFA and the magnetic properties of the alloy powders can be improved with proper metalloid admixture, among which the amorphous Fe 72 P 7 B 7 C 7 Si 7 alloy powder with high saturation magnetization and low coercivity can be obtained. The amorphous Fe 72 P 7 B 7 C 7 Si 7 alloy powder also exhibits good capability in degrading methylene blue dyes, and the optimal conditions for degradation processing are explored. Highlights • Amorphous Fe 72 P 7 B 7 C 7 Si 7 alloy powder has been prepared by mechanical alloying technology. • Metalloid admixture results in the high amorphous forming ability and good soft magnetic properties. • The amorphous Fe 72 P 7 B 7 C 7 Si 7 alloy powder exhibits good capability in degrading methylene blue dyes. [ABSTRACT FROM AUTHOR]

Abstract: The paper describes the physical, chemical, mechanical and thermal properties of 40P2O5–24MgO–16CaO–16Na2O–4Fe2O3 phosphate glass fibres. The initial mechanical properties of the fibres were determined to examine changes of these properties over time and also due to the variation of fibre diameter. A theoretical chain length of the fibres is calculated and that was validated using high resolution X-ray photoelectron spectroscopy (XPS) analysis. These fibres were degraded for 12weeks in deionised water with pH adjusted to ~7.4 at 37°C. Mass loss percentage, change of pH, degradation rate and the mechanical properties of the degraded fibres were determined. An XPS analysis of the 12week degraded fibre was conducted without etching and after 40min etching from the degraded surface. The elemental percentages of fibres degraded for different time periods were determined using energy dispersive X-ray (EDX) analysis. Scanning electron microscopy (SEM) analysis of the non-degraded and degraded fibres was also presented in order to assess changes in the fibre surface during degradation. The evolving surface of these water-soluble fibres was further characterised by Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The works completely elucidated the chemical nature and degradation pattern of the bulk fibre surface of this glass composition. [Copyright &y& Elsevier]

• The Fe 81 B 10 C 9 amorphous alloy has higher degradation activity, longer service life and self-cleaning performance than the Fe 81 B 10 P 9 amorphous alloy. • The Fe 81 B 10 C 9 amorphous alloy exhibits the inhomogenous corrosion pits while the Fe 81 B 10 P 9 amorphous alloy shows homogeneous corrosion. • The star-shaped C-rich corrosion pits in Fe 81 B 10 C 9 amorphous alloy can contribute to the self-peeling of the degradation products. The degradation behaviors of Fe 81 B 10 C 9 and Fe 81 B 10 P 9 amorphous alloys in methylene blue (MB) solution by Fenton-like method were explored. The Fe 81 B 10 C 9 amorphous alloy has higher degradation activity, longer service life and self-cleaning performance than the Fe 81 B 10 P 9 amorphous alloy. The results have verified that the FeBC amorphous ribbon exhibits unique corrosion morphological characteristics with regular star-shaped C-rich corrosion pits while the Fe 81 B 10 P 9 amorphous alloy shows homogeneous corrosion. The existence of star-shaped C-rich corrosion pits is associated with the formation of the galvanic cell structure between this C-rich pits and the amorphous base (C-poor), which can contribute to the accelerating of Fe atoms to lose electrons and the self-peeling of the degradation products. This work has important implications in understanding the high degradation activity and long service life of FeBC amorphous alloys in the treatment of dye wastewater by Fenton-like method. [ABSTRACT FROM AUTHOR]

• A nanoscale layer rich of small atoms (B/C) near the surface of Fe 81 B 10 C 9 amorphous ribbon was obtained. • The existence of the rich small atoms layer can satisfy the higher degradation capability. • The higher degradation efficiency has been attributed to the galvanic cell structure. A nanoscale layer rich of small atoms (B and/or C) near the surface in the Fe 81 B 10 C 9 amorphous ribbon was obtained by annealing the melt-spun ribbon at 523K. And the nanoscale chemical inhomogeneous layer was verified from the cross-section of the ribbon through the surface to the center by EPMA and TEM. The existence of the rich small atoms layer can satisfy the higher degradation capability for both electron transfer acceleration and easier contaminant removal on degrading methylene blue solutions in Fenton-like system. The higher degradation efficiency has been attributed to the galvanic cell structure formed between this nanoscale small atom rich layer and the amorphous base. This work provides a novel approach to obtain chemical inhomogeneity to enhance the degradation efficiency. [ABSTRACT FROM AUTHOR]