Micropillars with diameters of 1 and 3.8 m were fabricated from Mg-based metallic glasses using focus ion beam, and then tested in compression at strain rates ranging from 6 ϫ 10 −5 to 6 ϫ 10 −1 s −1. The apparent yield strength of the micropillars is 1342-1580 MPa, or 60%-100% increment over the bulk specimens. This strength increase can be rationalized using the Weibull statistics for brittle materials, and the Weibull modulus of the Mg-based metallic glasses is estimated to be about 35. Preliminary results indicated that the number of shear bands increased with the sample size and strain rates.

Optical reflectivity and electrical resistivity of multi-component AgMgAl alloys, both crystalline and amorphous, were measured. The crystalline alloys exhibit high reflection in infrared region but a steeper drop in visible and ultraviolet regions. By contrast, amorphous alloys show a lower but relatively uniform reflectivity in the visible and infrared regions. In both cases, the reflectivity was observed to scale with the square root of electrical resistivity. The scaling law was explained based on classical reflection theory. The different scaling factors for crystalline and amorphous alloys could be rationalized by the difference in the mean free time of charge carriers. V

Mg-AZ31 based composites with 10{20 vol% nano-sized ZrO 2 and 5{10 vol% nano-sized SiO 2 particles were fabricated by friction stir processing (FSP). The clusters of the nano-ZrO 2 and nano-SiO 2 particles, measuring 180-300 nm in average, were relatively uniformly dispersed. The average grain size of the Mg matrixes of the composites varied within 2-4 mm after four FSP passes. No evident interfacial product between the ZrO 2 particles and Mg matrix was found during the FSP mixing ZrO 2 into Mg-AZ31. However, significant chemical reactions occurred at the Mg/SiO 2 interface to form the Mg 2 Si phase. The mechanical responses of the resulting nano-composites in terms of hardness and tensile properties of these Mg/nano-ZrO 2 and Mg/nano-SiO 2 composites were examined and compared. The grain refinements and the corresponding hardening mechanisms are also analyzed and discussed.

High glass-forming ability correlated with fragility of Mg-Cu(Ag)-Gd alloysIn this study, the viscous flow behavior and thermomechanical properties of Mg 65 Cu 25−x B x Gd 10 ͑x = 0 and 3 at. %͒ bulk metallic glasses ͑BMGs͒ in the supercooled liquid region have been investigated by using differential scanning calorimetry and thermomechanical analyzer. It has been found that the fragility of the supercooled liquid is reduced by the boron addition, thus, degrading the deformability. This conclusion is supported by the many other extracted parameters. Thus, even with much higher hardness, the B-additive Mg based BMG will be more difficult to be formed, which appears to be a negative factor in applying in the microforming or nanoimprinting industry.