Effects of high-intensity pulsed ion beam irradiation on the structural thermal stability of Fe80Si7.43B12.57 metallic glass

• Published in: Fusion engineering and design Vol. 138; pp. 16 - 23
• Main Authors: Zhang, Qi, Mei, Xianxiu, Guan, Tong, Zhang, Xiaonan, Remnev, Gennady E., Pavlov, Sergey K., Wang, Younian
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-01-2019
• Subjects: Fe80Si7.43B12.57; High-intensity pulsed ion beam; Metallic glass; Thermal stability; High-intensity pulsed ion beam; Fe80Si7.43B12.57; Metallic glass; Thermal stability
• ISSN: 0920-3796; 1873-7196
• DOI: 10.1016/j.fusengdes.2018.10.012

Fig. 1. The cross-sectional TEM images of Fe80Si7.43B12.57 metallic glass after being irradiated for 300 times. (a) cross-sectional TEM morphology, the inset is the SAED; (b)–(d) HRTEM image corresponding to the region I, II, III in (a). The white ellipse marks the crystalline ordered structure.
This paper used TEM for the microstructure analysis of metallic glass Fe80Si7.43B12.57 after the irradiation at a pulse number of 300 times. Fig. 1 shows the cross-sectional TEM images of Fe-based metallic glass after HIPIB irradiation with an energy density of 0.2–0.3 J/cm2 and a pulse number of 300 times. It could be observed from the images that the atomic arrangement in different regions are disordered. Within the range of about 1 μm from the surface of the metallic glass (Fig. 1b–d), the atoms are aggregated and the free volume increases. The arrangement of atomic structures within the ion range region (about 1 μm) becomes uneven, especially at the near surface (about 200 nm from the surface, Fig. 1b). A small amount of crystalline ordered arrangement (white ellipse) can be seen from Fig. 1b–d. The selected area electron diffraction image contains a few rings from the ordered structure in addition to the halo of the amorphous phase, but the metallic glass still retains the amorphous structure.
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•Metallic glass could maintain amorphous state after HIPIB irradiation.•The atomic arrangement of the metallic glass become inhomogeneous after HIPIB irradiation.•There is a small amount of ordered atoms arrangement on the near surface of metallic glass at the number of pulses of 300.•The surface reflectance of the metallic glass decreased slightly after irradiation.
A high-intensity pulsed ion beam was used to irradiate Fe80Si7.43B12.57 metallic glass at different energy densities and numbers of pulses to study its structural thermal stability. A large number of round holes and a few bumps appeared on the surface of the glass after 300 pulses. No obvious damage was observed on the surface after irradiation at different energy densities. High-resolution transmission electron microscopy showed that this irradiation had a strong influence on the near-surface atomic arrangement of the glass. Irradiation induced strong migration and aggregation of atoms within the glass, causing an uneven atomic arrangement. Although there was an ordered arrangement of atoms, the metallic glass remained amorphous. The surface reflectivity of the metallic glass decreased slightly after irradiation. The number of irradiation pulses had greater impact on this Fe-based metallic glass than their energy density.