Usually, monolithic bulk metallic glasses undergo inhomogeneous plastic deformation and exhibit poor ductility (<2%) at room temperature. We report a newly developed Pd–Si binary bulk metallic glass, which exhibits a uniform plastic deformation and a large plastic engineering strain of 82% and a plastic true strain of 170%, together with initial strain hardening, slight strain softening and final strain hardening characteristics. The uniform shear deformation and the ultrahigh plasticity are mainly attributed to strain hardening, which results from the nanoscale inhomogeneity due to liquid phase separation. The formed nanoscale inhomogeneity will hinder, deflect, and bifurcate the propagation of shear bands.

Fe-based bulk metallic glasses usually exhibit very poor ductility (<0.5%), which has limited their applications. Here the authors report an Fe-based bulk metallic glass which shows a plastic strain of ∼5.2%, together with high strength and distinct strain-hardening characteristics. Its yield strength is ∼2.32GPa, while the ultimate strength is ∼2.80GPa due to the strain-hardening effect. Multiple shear bands and related shear ledges are observed on the deformed specimen. The high plasticity and strain hardening are attributed to the nanoscale inhomogeneity that resulted from liquid phase separation, which can hinder the propagation of shear bands and promote multiple shearing.

Preparation of surface enhanced Raman scattering (SERS) nanostructures with both high sensitivity as well as high reproducibility has always been difficult and costly for routine SERS detection. Here we demonstrate air-stable metallic glassy nanowire arrays (MGNWAs), which were prepared by a cheap and rapid die nanoimprinting technique, could exhibit high SERS enhancement factor (EF) as well as excellent reproducibility. It shows that Pd40.5Ni40.5P19 MGNWA with nanowires of 55 nm in diameter and 100 nm in pitch possesses high SERS activity with an EF of 1.1 × 105, which is 1–3 orders of magnitudes higher than that of the reported crystal Ni-based nanostructures, and an excellent reproducibility with a relative standard deviation of 9.60% measured by 121 points over an area of 100 μm*100 μm. This method offers an easy, rapid, and low-cost way to prepare highly sensitive and reproducible SERS substrates and makes the SERS more practicable.

By using a simple and low-cost arc-discharge method in deionized water, high purity SiC/SiOx nanocables have been synthesized in large-scale. The synthesized SiC/SiOx nanocables consist of an uniform cubic β-SiC core and an amorphous silicon oxide shell. They are about several hundred nanometres to several microns in length and the smallest average diameter of the β-SiC core is only about 5 nm, which may be attributed to the arc-discharge in deionized water approach and to the constraint of the outer sheath. The diameters of the as-grown nanocables can be controlled through adjusting the processing parameters. The SiC/SiOx nanocables emit stable violet-blue light at wavelengths of about 315 nm and 360-400 nm. Compared to the reported results in β-SiC nanowires or nanocables, the photoluminescence of the synthesized nanocables shows significant blueshift, which is resulted from the small diameter of the β-SiC core. The photoluminescence intensity can be enhanced by annealing the as-prepared SiC/SiOx nanocables.

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